Why does ice float on water? by Matthew Koh

Justyn Sun DFST2A04

2021-04-17 12:05:59 UTC

A substance floats if it is less dense or has less mass per unit volume. Generally, substances in solid state are denser than substances in liquid state. However, this is not the case for water.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined together by covalent bonding,

However, the oxygen atom pulls on these negatively-charged electrons much stronger than the hydrogen atoms can. As a result, the electrons tend to move closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposite charges attract, the slight charges on different molecules interact with each other. These interactions are called hydrogen bonds. Water molecules are attracted to each other by hydrogen bonds between the positively-charged hydrogen atoms and negatively charged oxygen atom.

In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

However, as the water cools down, it starts to form into its crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting too close. The result is a structure that is slightly less dense than liquid water.

Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a liter of ice weighs less than liter water. The heavier water displaces the lighter ice, so ice floats to the top.

Hence, ice floats on water.

Helmenstine, A. (2020). Scientific Explanation of Why Ice Floats. Retrieved 17 April 2021, from https://www.thoughtco.com/why-does-ice-float-604304

Rigby, S. (2021). Why does ice float on water?. Retrieved 17 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Yeo Yi En DFST2A04

2021-04-18 09:15:52 UTC

Generally, for an object to have buoyancy, the object should be less dense than the liquid.

The reason behind why ice floats on water is due to the differences in densities.

Most of the time, the solid form of the material is usually denser than the liquid, but water is a unique case as the water molecules are affected by a phenomenon known as hydrogen bonding.

Since oxygen is very electronegative, there is usually a slightly negative charge on the oxygen end and a slightly positive charge at the hydrogen end of the water molecule. As water cools down at lower temperatures, it starts to form a rigid crystal honeycomb lattice structure. While molecules with positively-charged ends and negatively-charged ends attract each other due to opposite charges, the same/like charges repel each other apart.

This results in the structure having more spaces between, resulting in ice being less dense than liquid water due to ice having a greater volume than water, while mass remains constant. The water molecules in ice take up about 9% more space than liquid water, which means ice is about 9% less dense than water.

Therefore, ice is less dense than water, allowing ice to be able to float on water.

Rigby, S. (2021). Why does ice float on water? Retrieved 18 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Why Does Ice Float in Water? (2021). Retrieved 18 April 2021, from https://wonderopolis.org/wonder/why-does-ice-float-in-water

KNOWLEDGE, G., & Goyal, S. (2021). What is the reason behind floating ice on water. Retrieved 18 April 2021, from https://www.jagranjosh.com/general-knowledge/do-you-know-why-does-ice-floats-on-water-1505475725-1

Bryan Ngo DFST2A03

2021-04-20 12:39:16 UTC

Ice floats on water because it is less dense than water.

When water freezes into its solid form, its molecules are able to form more stable hydrogen bonds, preventing them from interacting with one another.

Since, the molecules are not moving, they are not able to form as many hydrogen bonds with other water molecules.

This leads to ice water molecules not being as close together, thus reducing its density.

By using Archimedes’ principle, the upward buoyant force pushing against the submerged object is equal to the weight of the displaced water. Volume of object = Volume of Water.

Weight = mass x acceleration due to gravity.

Hence, for an object to be buoyant, the weight of the object must be equal to the weight of the water. g is constant, mass of object and water are the same.

Mass = Density x Volume

Since volume of the water is equal to the volume of the object, density changes.

Since, the density is lower in ice, the upward force causes ice to float on water.

Helmenstine, Anne Marie, Ph.D. (2020, August 28). Ice and the Density of Water. Retrieved 20 April 2021, from https://www.thoughtco.com/why-does-ice-float-604304

Britannica, T. Editors of Encyclopaedia (2020, May 29). Archimedes' principle. Encyclopedia Britannica. Retrieved 20 April 2021, from https://www.britannica.com/science/Archimedes-principle

2021-04-20 12:59:04 UTC

2021-04-20 13:09:04 UTC

Roshan DFST/2A/04

2021-04-20 18:49:38 UTC

Ice floats on water as it is less dense than water despite it being a solid. This is due to hydrogen bonding within the water molecule when temperature of the water decreases. Water is made up of 2 hydrogen atoms covalently bonded to an oxygen atom. However, the oxygen atoms has a stronger pull on the negatively charged electrons as compared to the hydrogen atoms. This results in the electrons to be closer to the oxygen atom resulting in a slight negative-charge around the oxygen end, and a slight positive-charge around the hydrogen end. This results in hydrogen bonds being formed between water molecules. When the temperature decreases, water starts to form crystal lattice structures. However due to the slight positive and negative charges of the water molecules, the same charges repel each other preventing the molecules from getting too close. This results in a structure that has more space causing the volume to increase but the mass remains constant resulting in ice less dense than water. Thus, ice floats on water.

Rigby, S. (2021). Why does ice float on water? Retrieved 18 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Brian DFST/2A/04

2021-04-21 03:10:44 UTC

A substance floats if it is less dense, or less mass per unit volume, than other substances in a mixture. For an object to be able to float, it has to displace a weight of fluid equal to its own weight.

Water reaches its maximum density at 4°C (40°F). As it cools further and freezes into ice, it becomes less dense. On the other hand, most substances are most dense in their solid (frozen) state than in their liquid state. Water is different due to hydrogen bonding.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined to each other with covalent bonds. Water molecules are also attracted to each other by weaker hydrogen bonds between the positively-charged hydrogen atoms and the negatively charged oxygen atoms of neighbouring water molecules.

As water cools to below 4 °C, the kinetic energy decreases so the molecules move around less quickly. They lack the energy to move and break and form bonds so easily. Instead, they form more hydrogen bonds with other water molecules to form hexagonal crystal lattice known as ice. They form these structures to keep the negatively charged oxygen molecules apart. In the middle of the hexagons, there is a lot of empty space.

Since ice is about 9% less dense than liquid water, it takes up about 9% more space than water. The heavier water displaces the lighter ice, so ice floats to the top. As a result, lakes and rivers freezes from the top to bottom, allowing fish to survive even when the surface of water is frozen over. If ice sank, the water would be displaced to the top and exposed to colder temperature, forcing rivers and lakes to fill with ice and freeze solid.

Helmenstine, A.M. (2020, February 3). Ice and the Density of Water. Retrieved 19 April 2021, from

https://www.thoughtco.com/why-does-ice-float-604304.

Rigby, S. (2021, February 10). Why does ice float on water? Retrieved 19 April 2021, from

https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Mairaa DFST/2A/04

2021-04-21 05:08:06 UTC

Ice is about 9% less dense than water. Since water is heavier than ice, hence ice will be displaced causing it to float on water. When water is cooled, the molecules are brought closer together. Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When water undergo freezing he hydrogen bonds hold the negatively-charged oxygen atoms apart, which causes ice to be less dense than water. For water, the density decreases as temperature decreases. When water is being frozen, the temperature decreases causing the density to decrease too. Therefore, ice floats on water due to its lighter density.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 21 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Why does ice float? | The Children's Museum of Indianapolis. Childrensmuseum.org. Retrieved 21 April 2021, from https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!.

Apex DFST/2A/04

2021-04-22 15:52:27 UTC

Why does ice float on water? To answer this question, firstly, we must explain why something floats on water. For example, for A to float on B, the density of A must be lesser than the density of B. A is then less dense and thus will float on B.

Mass refers to the measure of the amount of matter in a body while the volume is the amount of space the body occupies. Density is thus the measure of an object’s mass per volume (Mass/Volume), simply put, how much of the space does the amount of matter takes up.

Ice is formed from freezing water, where water molecules is held by hydrogen bonds H-O-H. As water is a polar molecule, when the temperature decreases, the bonds will align in a way that the volume of the water will increase as it becomes frozen to form ice.

However, an increase in size does not mean that the ice has become denser. The ice did in fact expand when it freezes from water, however the ice increased its own volume (How much space the body occupies) without increasing its mass (amount of matter the body occupies). As the volume increases, the density of ice will thus decrease and become less dense than the water, and therefore float on water.

Socratic.org. 2020. Why does ice float on water? | Socratic. [online] Available at: [Accessed 22 April 2021].

Hwee Min DFST/2A/05

2021-04-23 07:21:47 UTC

A water molecule is composed of an oxygen atom and two hydrogen atoms which are covalently bonded. Hydrogen bonds are also present between water molecules. When water cools to below four degrees Celsius, a crystal lattice structure known as ice forms.

The same mass of water and the same mass of ice have different densities. Ice is approximately 9% less dense than water, taking up 9% less space than the same mass of liquid water. This difference in density is because ice has a very different structure than liquid water, in that the molecules in ice align themselves in regular lattice structure than randomly in liquid state. The lattice arrangement allows water molecules to be more spread out than in liquid, causing ice to be less dense than water. Since the heavier water displaces the lighter ice, ice floats on water.

Resources:
United States Geological Survey. Water Density [online]. Available from: www.usgs.gov/special-topic/water-science-school/science/water-density?qt-science_center_objects=0#qt-science_center_objects [Accessed 23 April 2021]

Anne Marie Helmenstine, P.D., 2020. Scientific Explanation of Why Ice Floats. ThoughtCo. Available from: http://www.thoughtco.com/why-does-ice-float-604304 [Accessed 23 April 2021].

Rigby, S., 2021. Why does ice float on water? BBC Science Focus Magazine. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 23 April 2021].

jolene DFST/2A/04

2021-04-23 07:52:25 UTC

ice is about 9% more dense than water. since water is more dense than ice, Water has a density of 1.0 gm/cubic cm and ice has a density of 0.931 gm/cubic cm.
hydrogen bonds form when water freezes into ice, allow molecules to be further apart thus decreasing the overall density and water molecules in ice takes up about 9% more space than liquid water.
when water freezes into ice, molecules form a more stable hydrogen bonds, locking the the molecules in position, this ensure that they cannot form as many hydrogen bond as water.
this results to the water molecules in ice not being as close together compared to liquid water, thus ice floats on water.

GDPR. Byjus.com. Retrieved 23 April 2021, from https://byjus.com/questions/why-does-ice-floats-on-water/.

raine DFST/2A/04

2021-04-23 08:30:29 UTC

ice is actually about 9% less dense than water. Since the water is heavier, it displaces the lighter ice, causing the ice to float to the top.
when a liquid is cooled, more molecules are brought closer together and need to be accommodated in a smaller area. this results in most solids having a greater density than liquids. water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. when water cools, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart, which prevents the ice from becoming any denser. for water, the density actually decreases along with a decrease in temperature, this causes ice to be less dense than water and ice to float on water.

resources :
Byrd, L. (2019). Why does ice float? | The Children's Museum of Indianapolis. Retrieved 23 April 2021, from https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%

Min Min DFST2A04

2021-04-23 13:16:34 UTC

Ice floats on water because it is less dense than water. This is due to the presence of hydrogen bonds between the oxygen and hydrogen atoms. In liquid state, the hydrogen bonds break and molecules are able to slide over one another. So when water freezes and cools, a crystal lattice structure forms, forming solid ice. The broken molecules which are of like charges will repel and prevent the molecules from getting close. Hence, ice has lesser density than water which has more hydrogen bonds.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 23 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Qi Qi DFST 2A 04

2021-04-23 13:32:36 UTC

water solidifies to become ice because of hydrogen bonds forming together into a cystalline structure. In water, hydrogen bonds constantly break and form from one another, but when the temperature of water cools down, the kinetic energy of these particles start to decrease, causing them to vibrate less frequently, thus, more hydrogen bonds are forming than breaking which causes the formation of many hydrogen bonds joined together to form a giant crystal structure, which is ice. This causes Ice to be less dense than water and therefore it can float on water as its molecular structure is more organised than the disorganised structure of liquid water.
Youtube.com. 2021. Before you continue to YouTube. [online] Available at: [Accessed 23 April 2021].

kelly DFST 2A/05

2021-04-23 16:27:14 UTC

kelly DFST/2A/05

2021-04-23 16:30:41 UTC

ice is less dense than water.
Water reaches its maximum density at 4°C (40°F). As it cools further and freezes into ice, it actually becomes less dense. On the other hand, most substances are most dense in their solid (frozen) state than in their liquid state. Water is different because of hydrogen bonding.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined to each other with covalent bonds. Water molecules are also attracted to each other by weaker chemical bonds (hydrogen bonds) between the positively-charged hydrogen atoms and the negatively charged oxygen atoms of neighbouring water molecules. As the water cools to below 4°C, the hydrogen bonds adjust to hold the negatively charged oxygen atoms apart. This produces a crystal lattice commonly known as ice.

Helmenstine, Anne Marie, Ph.D. "Ice and the Density of Water." ThoughtCo, Aug. 28, 2020, https://www.thoughtco.com/why-does-ice-float-604304.

kye xiang dfst2A04

2021-04-24 02:52:14 UTC

Ice is about 9% less dense than water. Hence, water displaces ice, causing the latter to float on water. Most solids are denser than liquids, explaining why they sink. However, water is a unique scenario, whereby molecules in water are affected by hydrogen bonding. A v-shaped water molecule comprises of an oxygen and two hydrogen atoms, held together by covalent bonds. Individual water molecules are held together by hydrogen bonds. Oygen atom attracts these negatively-charged electrons stronger than the hydrogen atoms can. Hence the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms, leaving the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end. As molecules move around in liquid form, hydrogen bonds form and break repeatedly, allowing individual molecules to slide over each other. As water cools down, it forms a crystal lattice structure, which is ice. While the molecules want to form hydrogen bonds between the slight positive and slight negative charges, the same charges repel each other, preventing the molecules from getting too close. Therefore, ice is less dense than water.

Children's Museum Indianapolis[n.d.], Why does ice float[online]? Retrieved from:

Rigby, S.,[2021], Science Focus, Why does ice float on water?[online], retrieved from:

Nicole DFST2A05

2021-04-24 05:41:00 UTC

Ice floats on water as it is about 9% less dense than water. Since water is heavier, it displaces the lighter ice, causing the ice to float to the top. Water reaches its maximum density at 4°C. As it cools further and freezes into ice, it becomes less dense.

This is because of the hydrogen bonds in water. Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When water cools, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart. As such, a structure with many empty spaces is formed, which is known as the solid substance ice. Ice has a larger volume than water and thus a lower density than water, allowing it to float on water.

Helmenstine, A., M. (2020, February 03). Ice and the Density of Water. Retrieved from: https://www.thoughtco.com/why-does-ice-float-604304

D’Augustino, T. (2016, February 16). Exploring our world: Why does ice float? Retrieved from: https://www.canr.msu.edu/news/exploring_our_world_why_does_ice_float

Byrd-McDevitt, L. (2016, December 5). Why does ice float? Retrieved from: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!

Yong Seng DFST2A03

2021-04-24 06:54:18 UTC

Ice floats on water because its density is 9% lesser than water. In general, solids are denser than liquids. However, water molecules are affected by a phenomenon known as hydrogen bonding. A water molecule is made up of an oxygen atom in the center, with one hydrogen atom on each side. They are held together by covalent bonds, where two atoms share a pair of electrons. But the oxygen atom pulls on the negatively charged electrons more strongly than the hydrogen atom. This results in a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end. And since opposites attracts, the slight charges on different molecules interact with each other, causing hydrogen bonds to form.

At liquid state, the water molecules are free to move around and hydrogen bonds form and break over and over. But as the temperature decreases, a crystal lattice structure starts to form. The molecules want to form hydrogen bonds between the slightly positive and negative charges, however like charges will repel each other, which prevents the molecules from getting too close, resulting in a structure that is less dense than water.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 24 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Samantha DFST2A01

2021-04-24 07:58:21 UTC

Ice is 9% less dense than water. This is because water and ice is a rather special case (does not obey the law of solids is denser than liquid) whereby the water molecules in water are affected by hydrogen bonding. Each water molecules contains 2 hydrogen atoms and one oxgen atoms and are held together by covalent bonds.

The oxygen atom pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. Hence the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms.

In liquid form ( as the ice melt) , as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

But as the water from ice cools down , it starts to form into its crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting too close. The result is a structure that is slightly less dense than liquid water.

This hence causes the ice to be less dense than water resulting in the ice to float up to the surface of water.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 24 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/. [ Accessed on 24th April 2021 ]

Joy DFST2A05

2021-04-24 08:54:51 UTC

Ice floats on water as it is 9% less dense than water.

At 4°C, water reaches its maximum density. When it freezes into ice, it becomes less dense due to hydrogen bonding. Water molecules are composed of one oxygen atom and two hydrogen atoms joined together by covalent bonds. The water molecules are also attracted to one another due to the hydrogen bonding that exist between the positively-charged hydrogen atoms and the negatively charged oxygen of the neighbouring water molecules.

However, when the temperature of water is below 4°C, the kinetic energy of the water molecules decreases thus they lack the energy to move, break and form bonds as easily as before. The water molecules then form more hydrogen bonds with one another resulting in the formation of a hexagonal crystal lattice in order to hold the negatively charged oxygen atoms apart. The hexagonal crystal lattice formed is known as ice.

Since ice is less dense than water, the denser water displaces by the less dense ice, therefore ice floats on water.

Helmenstine, A.M., 2020. Scientific Explanation of Why Ice Floats. ThoughtCo. Available at:

Motivans, E., 2021. The reason why ice floats. ZME Science. Available at: <https://www.zmescience.com/other/science-abc/reason-ice-floats/>

Joseph DFST2A05

2021-04-24 09:39:03 UTC

Before ice is formed, it expands when cooled at a temperature of approximately 4°C and below. When it freezes and becomes ice, it is now 9% less dense than water. As we all know about density is mass/volume. Since the relative mass of the ice remain the same but the volume increases, the final density of ice is less than water. Water has oxygen atom which pulls on these negatively-charged electrons that are much more strongly than the hydrogen atoms in water can. As a result, the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites attract, the slight charges on different molecules interact with each other. These interactions are called hydrogen bonding.

In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

Ong Sin Min DFST2A03

2021-04-24 10:16:48 UTC

A substance floats if it is less dense than other components in a mixture. This explains why does ice floats on water as ice is 9% less dense than water. In fact, most of substances are more dense in their solid state than in their liquid state but water is different due to their hydrogen bonding.

One water molecule comprises of one oxygen atom and two hydrogen atoms which are tightly held together by covalent bonds. Water molecules are attracted to each other by hydrogen bonds between positively-charged hydrogen atoms and negatively-charged oxygen atoms. As the water is cooled down, more hydrogen bonds are formed between water molecules to produce a crystal lattice structure known as ice in order to keep the negatively-charged oxygen atoms apart. More spaces are created inside the crystal lattice structure, resulting ice to be less dense than liquid water.

Helmenstine, A. M. (2020, February 03). Ice and the Density of Water. ThoughtCo.. Retrieved from: https://www.thoughtco.com/why-does-ice-float-604304

Rigby, S. (2021, February 10). Why does ice float on water? Science Focus. Retrieved from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Chen Miao Hua DFST2A04

2021-04-24 10:34:42 UTC

Ice floats on water because ice is less dense than water. When water freezes, it's molecules starts to form into crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, therefore the molecules are spaced further apart. Since ice is less dense than water, ice floats on water.

Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: [Accessed 24 April 2021].

Shaa'irah DFST/2A/05

2021-04-24 12:38:10 UTC

A water molecule is made from one oxygen atom and two hydrogen atoms jointed to each other via covalent bonds. Water molecules are also attracted to one another by hydrogen bonds between the positively charged hydrogen atoms and the negatively charged oxygen atoms of other water molecules. As the water cools to below 4°C, the hydrogen bonds adjust to hold the negatively charged oxygen atoms apart. Ice has a different structure than liquid water, in that the molecules align themselves in a regular lattice rather than more randomly as in the liquid form. This results in water molecules to be more spread out than in a liquid form. Therefore, ice floats on water because ice is less dense than water.

Resources:
Helmenstine A.M. 2020. Ice and the Density of Water [online]. Available at: [Accessed on: 24 April 2021]

U.S. Geological Survey. n.d. Water Density [online]. Availble at: [Accessed on: 24 April 2021]

Lim Yue Rong DFST/FT/2A/04

2021-04-24 13:46:05 UTC

When a substance is less dense or has less mass per unit volume than the other components in the mixture, it floats. Ice floats on water because ice is about 9% less dense than liquid water despite it being solid. Although most substances have a higher density in their solid form as compared to their liquid form, water acts differently in its solid form due to its hydrogen bonding.

A water molecule is made up of one oxygen atom covalently bonded to two hydrogen atoms. Oxygen is highly electronegative and the water molecule will have a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end. Since opposites attract, neighboring water molecules are slightly attracted to each other and form hydrogen bonds between the positively-charged hydrogen ends and the negatively-charged oxygen ends.

As water cools down to below 4℃, a crystal lattice structure is formed. However, as the water molecules form hydrogen bonds between the slight positive and negative charges, the same charges also repel each other and this prevents the water molecules from getting too close to each other. This forms pockets of space in between the structure, creating a structure that is slightly less dense than liquid water. So since ice has a larger volume and takes up about 9% more space than water, the ice is less dense and will float on water.

References:
Helmenstine, A. (2020). Scientific Explanation of Why Ice Floats. ThoughtCo. Retrieved 24 April 2021, from https://www.thoughtco.com/why-does-ice-float-604304.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 24 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Grace Ee DFST/FT/2A/05

2021-04-24 14:32:37 UTC

As the water molecules slide past each other in liquid water, hydrogen bonds are constantly formed and broken. When water freezes due to a drop in temperature, the water molecules form a crystalline shape that is maintained by hydrogen bonding. This is because the energy required to break the hydrogen bonds is insufficient. This makes ice less dense than water. The low density of water in its solid state is due to the way hydrogen bonds are oriented when it freezes. The water molecules are pulled apart than in liquid form. Therefore, since ice is less dense than water, it is able to float on water.

Biology LibreTexts. (2018). 2.2B: Water’s States: Gas, Liquid, and Solid. [online] Available at: https://bio.libretexts.org/Bookshelves/Introductory_and_General_Biology/Book%3A_General_Biology_(Boundless)/2%3A_The_Chemical_Foundation_of_Life/2.2%3A_Water/2.2B%3A_Waters_States%3A_Gas_Liquid_and_Solid#:~:text=Solid%20water%2C%20or%20ice%2C%20is,apart%2C%20which%20lowers%20the%20density.&text=Because%20ice%20is%20less%20dense,at%20the%20surface%20of%20water. [Accessed 24 Apr. 2021].

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Angie Liew DFST/2A/03

angieliew — 2021-04-24 14:45:46 UTC

Solids are denser than liquid, this means that solid will sink. Ice which is in solid state float on water is an exceptional case. This is because ice is about 9% less dense as compared to water, and it will also take up 9% more space than water when placed in a container. The molecules in water are affected by hydrogen bonding.

Water molecule is made of two positively charged hydrogen atoms and one negatively oxygen atom which is connected by very strong chemical bonds known as covalent bonds. The oxygen atom pulls on negatively-charged electrons more strongly than the hydrogen atoms can. As a result, the electrons tend to be closer to the oxygen atom as compared to hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites charge attracts, the charge on different molecules attracts forming hydrogen bonds.

In liquid form, water molecules slide past one another around, hydrogen bonds form and break repeatedly. When the water is exposed to cold temperature, crystal lattice structure begins to form. As the molecules form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting closer. This resulted the structure to be slightly less dense than liquid water, thus float on water.

Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: [Accessed 24 April 2021].

Units.miamioh.edu. 2008. Why Does Ice Float?. [online] Available at: [Accessed 24 April 2021].

Darren DFST/2A/01

2021-04-24 14:56:24 UTC

Hmmm interesting. You would expect ice to be denser and sink since it a solid. However, this is not the case for ice. So, why is ice, a solid, less dense than a liquid?

To answer the question let recap on the chemical structure of water. Water or H2O has 2 hydrogen atoms covalently bonded to oxygen. Since it has 2 lone pairs and a stearic number of 4 (2 lone pairs and 2 hydrogen atoms attached to oxygen), water has a molecular geometry of bent or V shaped with a bond angle of 104.5° between 2 hydrogen atoms in liquid state while 109° in solid state.

Whether water in solid or liquid state contains hydrogen bonds, which are constantly breaking and reforming between different water molecules. In liquid state, less water molecules are involved in hydrogen bonding than in solid state since it easier for hydrogen bonds to break. This also explains the smaller bond angle in liquid than solid state.

Liquid molecules have a smaller bond angle than ice and the molecules can be packed more tightly. Thus, the average number of water molecules in liquid is higher than ice. Furthermore, the average number of water molecules are also affected by temperature, with increasing temperature molecules gain kinetic energy, move faster and further.

Although temperature and bond angle affect density, bond angle has a higher effect on density. Thus, ice is less dense than water because the number of molecules is lesser and cannot be packed tightly as liquid water, which explain why ice is less dense although it has a low temperature.

Lower, S., 2021. 7.3: Hydrogen-Bonding and Water. [online] Chemistry LibreTexts. Available at: [Accessed 24 April 2021].

Teo Yui Ting DFST/FT/2A/05

2021-04-24 15:39:11 UTC

Ice floats on water because it is close to 9% less dense than water. In other words, the mass per volume of ice is lower than that of water.

Usually, solids are denser than liquids as the molecules in solids are packed tightly together in an orderly pattern to form a crystal lattice whereas molecules in liquids are packed less tightly together and are slightly further away from one another. Thus, for the same mass, liquids have a larger volume than solids, thus a lower density. However, this is not the case for water.

Due to the hydrogen bonding present in water, the negatively charged oxygen atoms tend to interact with the positively charged hydrogen atoms as opposite charges attract each other.

When water cools to its freezing point, the crystal lattice forms. The hydrogen bonds adjust to hold the negatively charged oxygen atoms apart, thus the molecules are further apart from one another. This results in a decrease of density.

Citations:

Rigby, S., 2021. Why does ice float on water? [online]. Science Focus. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 24 April 2021]

Helmenstine, Anne Marie, 2020. Ice and the Density of Water [online]. ThoughtCo.. Available from: https://www.thoughtco.com/why-does-ice-float-604304 [Accessed 24 April 2021]

Avan DFST/FT/2A/05

2021-04-24 15:56:47 UTC

When water freezes into ice, it becomes 9% less dense. Normally solids are denser than liquids as molecules are packed closer together in solids than they are in liquids, but water is an exception. Water molecules are affected by hydrogen bonding. When water cools into ice, it forms a crystal lattice structure, while adjacent water molecules want to form hydrogen bonds with each other, the same charges repel each other (since like charges repel), stopping the molecules from getting too close. This thus results in ice being less dense than water, causing it to float.

Rigby, S. (2021, February 10). Why does ice float on water? BBC Science Focus Magazine. https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Cheryl Siah DFST/FT/2A/04

2021-04-24 16:35:53 UTC

Despite how both ice and water are made up of H₂O molecules, ice has a lower density of 0.931 gm/cubic cm as compared to water which has a higher density of 1.0 gm/cubic cm, hence water floats in ice. The reason is because liquid water has a partially ordered structure in where hydrogen bonds are constantly being formed and breaking up. On the other hand, ice has a rigid lattice structure.

In liquid water each molecule is hydrogen bonded to approximately 3.4 other water molecules.

In ice each molecule is hydrogen bonded to 4 other molecules. The O-O distances between any two adjacent oxygen atom in ice is higher than the O-O distances between any two adjacent oxygen atom in liquid water. Because of ordered structure in ice there are less H20 molecules in a given space of volume. Since a cubic unit of ice has lower mass compared to a cubic unit of water, and density=mass/volume, ice has lower density than water, hence it floats in water.

Molecules, W. (2021). Why does ice float?. Retrieved 24 April 2021, from https://www.worldofmolecules.com/3D/why-does-ice-float.html

Kimberley DFST/FT/2A/03

2021-04-24 19:45:46 UTC

The denser the object, the more it will sink. Ice is a solid which should be densed, but it is actually 9% less dense than water. Since water is heavier so it displaces the lighter ice, causing ice to float to the top. Water (H₂O) consists of positively charged hydrogen atoms and negatively charged oxygen atoms. When water is at a low temperature, hydrogen bonds adjust to hold the negatively charged oxygen atoms apart. Since atoms are being held apart, this prevents the ice from becoming denser. For water, density decreases as temperature decreases. Hence causing ice to be less dense than water which is why ice floats on water.

Byrd-McDevitt, L., 2021. Why does ice float? | The Children's Museum of Indianapolis. [online] Childrensmuseum.org. Available at: [Accessed 24 April 2021].

Tan Wee Lin, Jezryne DFTS/FT/2A/04

2021-04-24 20:22:57 UTC

Ice floats on water as it is less dense compared to water. Ice is less dense due to the molecules in water being affected by hydrogen bonding. A water molecule is made up of one oxygen atom and two hydrogen atoms. The molecule is held together by covalent bonds, which is when two atoms share a pair of electrons.

The oxygen atom, being more electronegative, attracts the negatively charged electrons much more strongly than the hydrogen atoms. This results in a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end. The slight opposite charges on different molecules interact with each other. These interactions are called hydrogen bonds.

In the liquid form, molecules can move around and slide past each other causing hydrogen bonds to form and break repeatedly. However, ice is a solid which has a crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same charges repel each other, preventing the molecules from getting too close. This results in a structure that is slightly less dense than liquid water as the molecules are further apart. Hence, ice is less dense than water, causing it to float.

Rigby, S. (2021). Why does ice float on water? BBC Science Focus Magazine. Retrieved 25 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/ .

Rachel DFST/FT/2A/05

2021-04-25 02:03:59 UTC

Firstly, ice is about 9% less dense as compared to water. This means that ice takes up about 9% more space than water, so a liter of ice weighs less than a liter of water.

Water reaches its maximum density at 4 degree Celsius. As it cools further and freezes into ice, it actually becomes less dense.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined to each other with covalent bonds. Water molecules are also attracted to each other by weaker chemical bonds (hydrogen bonds) between the positively-charged hydrogen atoms and the negatively charged oxygen atoms of neighboring water molecules. As the water cools to below 4 degree Celsius, the hydrogen bonds adjust to hold the negatively charged oxygen atoms apart. This produces a crystal lattice, also known as ice.

Therefore, this suggests that the density of water decreases with a decreasing temperature. Since water is denser, it displaces the less dense ice, causing the ice to float on water.

ThoughtCo. 2020. Scientific Explanation of Why Ice Floats. [online] Available at: [Accessed 21 April 2021].

Childrensmuseum.org. 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Available at: [Accessed 21 April 2021].

Fang Yi DFST2A05

2021-04-25 02:24:42 UTC

Hydrogen bonds are present in water, between the positively-charged hydrogen atoms and negatively-charged oxygen atoms. At rtp, the bonds have high kinetic energy, allowing them to break and form continuously. This result in the water molecules having a disordered structure. However, at low temperatures the kinetic energy decreases such that these hydrogen bonds formed are more stable and will not break as easily. The water molecules at the low temperature, therefore, has an orderly arrangement. Due to the orderly arrangement, ice is less dense and thus floats on water.

References:
TED-Ed. (2013). Why does ice float in water? – George Zaiden and Charles Morton. [Video File]. Retrieved from: https://www.youtube.com/watch?v=UukRgqzk-KE

Amanda DFST 2A/02

amandatanqixin19 — 2021-04-25 03:30:58 UTC

The density of ice is lower than water at 0.931gm/cubic cm compared to water which has a density of 1.0gm/cubic cm. When water freezes into its solid form, the molecules are able to form more stable hydrogen bonds within the structure, locking them into positions. Since the molecules are unable to move around freely anymore, they are unable to form hydrogen bonds with other water molecules. This causes the water molecules in ice to have a higher intermolecular distance compared to water, thus allowing the density to decrease. The water molecules in water are able to move around freely as there are no hydrogen bonds present to hold lock the molecules in place. This suggests that the water molecules in water have a smaller intermolecular distance. Therefore, ice has a lower density compared to water.

References:
BYJUS. (n.d.). Why does ice floats on water? - BYJU’S Q&A. [online] Available at: https://byjus.com/questions/why-does-ice-floats-on-water/ [Accessed 25 Apr. 2021].

Lee Jiayi Cassandra DFST2A/05

2021-04-25 03:36:08 UTC

If ice floats on water, we can deduce that it should be less dense than water itself. Ice is 9% less dense than water

A molecule of water consists of one oxygen atom strongly bonded to two hydrogen atoms with covalent bonds. (H2O)

The weaker hydrogen bonds between the water molecules are how the molecules are attracted to one another.These form between the positively-charged hydrogen atoms and negatively-charged oxygen atoms in nearby water molecules.

When you freeze water (temperature of water decreases), the weaker hydrogen bonds begin to hold the negatively-charged oxygen atoms apart, forming a rigid crystal honeycomb structure we call ice. The water molecules in ice take up about 9% more space than liquid water. Hence, this shows that ice is about 9% less dense than water and can float on water.

References:

Why Does Ice Float in Water? (2021). Retrieved 25 April 2021, from https://wonderopolis.org/wonder/why-does-ice-float-in-water

Childrensmuseum.org. (2016) Why does ice float? | The Children's Museum of Indianapolis. Retrieved 25 April 2021, from https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water

Ong Chen Yu DFST/2A/05

ochenyu26 — 2021-04-25 03:47:50 UTC

Ice is less dense compared to water. As water gets below 4 °C, the kinetic energy decreases so the molecules don’t move around so much anymore. They don’t have the energy to move and break or form bonds so easily. Instead, they form a hexagonal lattice structure with water molecules using hydrogen bonds. These structures keep the negatively charged oxygen molecules apart. In the middle of the hexagons, there is a lot of empty space. Hence allowing ice to float.
Reference:
https://www.zmescience.com/other/science-abc/reason-ice-floats/

Xin Ning DFST2A03

xinning1920 — 2021-04-25 05:15:22 UTC

Ice is 9% less dense than water. Usually solids are denser than liquids, however ice is an exception. When a liquid is cooled, molecules are brought together and are packed into a smaller area, resulting in most solids having a greater density than liquids. On the other hand, water molecules consist of positively charged hydrogen atoms and negatively charged oxygen atoms. Thus, during cooling, the hydrogen bonds in water adjust to hold the negatively charged oxygen atoms apart, preventing the ice from becoming denser. Thus, the resulting ice is less dense than water and floats.

Reference:

Childrensmuseum.org. (2016) Why does ice float? | The Children's Museum of Indianapolis. Retrieved 25 April 2021, from https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water

Yi Xian DFSTA01

yixian20 — 2021-04-25 06:05:26 UTC

Any object that is less dense than water will float (Rigby, S., 2021). Since ice is approximately 9% less dense than water, the heavier water will displace the lighter ice, resulting in the ice floating to the top (Childrensmuseum, 2016)

Solids are denser than liquids most of the time, but ice is a special case due to hydrogen bonding between molecules of water. As water cools, a crystal lattice structure forms. When the water molecules start forming hydrogen bonds between the slight positive and negative charges, repulsion occurs between the the same-charges, stopping the water molecules from coming too close to each other. This results in a slightly less dense structure (ice) than liquid water (Rigby, S., 2021) that floats.

References:
Rigby, S., 2021. Why does ice float on water? BBC Science Focus Magazine. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/
[Accessed 25 April 2021]

Childrensmuseum, 2016. Why does ice float? | The Children's Museum of Indianapolis. Available from: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water [Accessed 25 April 2021]

Tong Suen DFST/2A/05

2021-04-25 08:33:06 UTC

Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a liter of ice weighs less than liter water. The heavier water displaces the lighter ice, so ice floats to the top.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined to each other with covalent bonds. Water molecules are also attracted to each other by weaker chemical bonds (hydrogen bonds) between the positively-charged hydrogen atoms and the negatively charged oxygen atoms of neighboring water molecules. As the water cools to below 4°C, the hydrogen bonds adjust to hold the negatively charged oxygen atoms apart, resulting in the formation of ice.Hence,this causes the ice to be less dense than water allowing it to float on water.

References:
Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/[Accessed 25 April 2021].

Helmenstine, A., 2020. Scientific Explanation of Why Ice Floats. [online] ThoughtCo. Available at: https://www.thoughtco.com/why-does-ice-float-604304
[Accessed 25 April 2021].

Faye DFST/2A/02

fayelim20 — 2021-04-25 08:38:52 UTC

Ice floats as it is less dense than water. Water's density can change with temperature, and upon freezing, water's density reduces about 9%. Water is a liquid while ice is a solid, this also plays a part in the difference in density between ice and water as the water molecules are more tightly and orderly packed (lattice structure) in ice versus in the liquid water, where the molecules can move more freely. Hence ice floats as it is less dense than water.
Usgs.gov. (2019). Water Density. [online] Available at: https://www.usgs.gov/special-topic/water-science-school/science/water-density?qt-science_center_objects=0#qt-science_center_objects [Accessed 25 Apr. 2021].

‌

Celeste Chong (DFST02)

2021-04-25 08:49:12 UTC

Ice can float on water as it is less dense than water.

Every water molecule consists of 2 hydrogen atoms bonded to 1 oxygen atom. Water molecules can form hydrogen bonds with one another. The partial negative charge on the oxygen of one molecule can form a hydrogen bond with the partial positive charge on the hydrogens of other molecules, forming a giant lattice structure.

At a high temperature, water molecules can bend, stretch, and move due to kinetic energy being greater than energy of hydrogen bonds. Hence, hydrogen bonds can be formed and broken repeatedly.

At a low temperature, the kinetic energy falls below the energy of hydrogen bonds. Hence, hydrogen bonds forms more frequently, creating a giant hexagonal lattice structure.

Due to the giant lattice structure in ice (solid) being less dense than the disordered structure in water (liquid), ice floats on water.

References:

TED-Ed, 2013. Why does ice float in water? - George Zaidan and Charles Morton. [video] Available at: [Accessed 25 April 2021].

Patrick DFST/2A/05

2021-04-25 08:52:55 UTC

A water molecule consists an oxygen atom that is strongly covalently bonded to two hydrogen atoms. Water molecules tend to attract each other by weaker hydrogen bonds. These bonds form between positively-charged hydrogen atoms and negatively-charged oxygen atoms. As water's temperature decreases, the hydrogen bonds hold the negatively-charged oxygen atoms apart forming a crystal lattice structure also known as ice, which takes up 9% more space than liquid water. The ice is 9% less dense as compared to water. Since the ice is less dense as compared to water, the ice will float in water.

References:
Wonderopolis.org. n.d. Why Does Ice Float in Water?. [online] Available at: https://wonderopolis.org/wonder/why-does-ice-float-in-water [Accessed 25 April 2021].

Jomane DFST/2A/05

2021-04-25 09:53:03 UTC

ice is actually about 9% less dense than water. Since the water is heavier, it displaces the lighter ice, causing the ice to float to the top. When a liquid is cooled, more molecules are brought closer together and need to be accommodated in a smaller area. This results in most solids having a greater density than liquids.
Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. It is a V-shaped molecule made up of one oxygen atom in the center with a hydrogen atom on each side. The molecule is held together by covalent bonds, which is when two atoms share a pair of electrons. When water cools, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms.
the oxygen atoms pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. As a result, the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites attract, the slight charges on different molecules interact with each other. These interactions are called hydrogen bonds.

Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: [Accessed 25 April 2021].

Childrensmuseum.org. 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Available at: [Accessed 25 April 2021].

Elaine Koh DFST/2A/03

2021-04-25 13:01:22 UTC

Ice is about 9% less dense than water. While water is heavier therefore ice floats on top of water.
when liquid is cooled, more molecules are packed closer together, which makes it more dense. however for water it consist hydrogen atoms and oxygen atoms. when water cools, hydrogen bonds holds oxygen atom preventing ice from becoming denser as before.
This shows that when the temperature of water decrease the density also decreases . Hence when the temperature of water decreases(which also means colder), water molecules(which is ice) will become denser.

Children's Museum. Why does ice float? [online] Available at: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!
[Accessed 25 April 2021]

Tze Jing DFST/2A/03

2021-04-25 13:11:01 UTC

Ice is around 9% less dense than water and hence floats on water. When water freezes, it expands. This is because water has hydrogen bonds between the oxygen and hydrogen molecules. In its liquid form, molecules can slide past each other and the hydrogen bonds can break and form. However, as water freezes into ice, it forms a crystal lattice structure. The molecules instead repel each other as the molecules from hydrogen bonds. This causes the water to expand as it turns into ice.

As the water expands, the volume of ice increases and it takes up more space. Since density is mass/ volume, when the volume increases, the density decreases as they are inversely proportional. Since the density of ice decreases, ice floats on water.

Rigby, S. (2021, February 10). Why does ice float on water? Retrieved April 25, 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Li Kewei DFST/2A/03

2021-04-25 13:15:47 UTC

This is due to ice's density being less than liquid water's density. Upon freezing, the density of ice decreases by about 9 percent. When water freezes into ice, hydrogen bonds are formed and the molecules are spaced apart, making them take more space, therefore the volume of ice is greater than that of water, density of ice is less than that of water.
A substance with a lower density than water can float on water. Therefore, ice floats on water.

USGS( 2021). Water Density. [online] Available at: [Accessed 25 April 2021].

Ng Jing Yang DFST/2A/05

2021-04-25 13:47:16 UTC

Ice floats on water as it has a lower density than water (around 9% less dense) due to hydrogen bonding. the heavier water displaces the lighter ice causing it to float.
water molecules are held together by strong covalent bonds. the more electronegative oxygen atom better attract negatively-charged electrons compared to the hydrogen atoms. As a result, the electrons tend to hover closer to the oxygen atom hence oxygen atom have a partial negative charge while hydrogen atoms have a partial positive charge. the partial charges on the water molecules interact with each other. giving rise to hydrogen bond.

In liquid form, as the molecules move around, hydrogen bonds form and break and the molecules can slip past each other.

Anne Marie Helmenstine, P. D. (2020, February 3). Scientific Explanation of Why Ice Floats. ThoughtCo. https://www.thoughtco.com/why-does-ice-float-604304.

Rigby, S. (2021, February 10). Why does ice float on water? BBC Science Focus Magazine. https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Gordon DFST/2A/03

2021-04-25 14:23:32 UTC

This is because ice is about 9% less dense than water. Anything that is less dense than water will get displaced by the water which causes it to float to the surface. Ice is less dense than water as there is the presence of positive charged hydrogen and negative charged oxygen atoms in water. There is a relationship between density and temperature for water where the lower the temperature of the water the less dense it is, this is due to the hydrogen bonds adjusting to hold the negatively charged oxygen atoms apart which in turn stops the density of ice from increasing. Since ice is obtained by cooling water, ice is naturally less dense than water and will hence float on water.

Reference:
Childrensmuseum.org. (2016) Why does ice float? | The Children's Museum of Indianapolis.
Available at: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water
Accessed [ 25 April 2021].

Ng Zi Qing DFST/2A/04

2021-04-25 14:42:37 UTC

Water molecules made up of one oxygen and 2 hydrogen. Two water bind together by hydrogen bond. When it cools down it started to form crystal lattice.Ice and water have different structure. Ice is a solid so they align themselves in lattice arrangement while water is in liquid form. Molecules of water wanted to form hydrogen bond between positive and negative charge and the same charges repel each othes stoping them to geet too close .So ice is more less dense than water.

Usgs.gov. (2019). Water Density. [online] Available at: https://www.usgs.gov/special-topic/water-science-school/science/water-density?qt-science_center_objects=0#qt-science_center_objects [Accessed 25 Apr. 2021].

Rigby, S. (2021, February 10). Why does ice float on water? BBC Science Focus Magazine. https://www.sciencefocus.com/science/why-does-ice-float-on-water/[Accessed 25 Apr. 2021].

Lee Xin Xuan DFST/2A/03

2021-04-25 14:58:44 UTC

Ice is 9% less dense as compared to water which causes it float. This is due to hydrogen bonding, the oxygen atom has a slight negative charge as it pulls on the electrons stronger than the hydrogen atoms, leaving the hydrogen atoms with a slight positive charge. As water cools down and form a crystal lattice structure, while the molecules want to form hydrogen bonds with the two opposite charges, the presence of the same charges repel each other, causing the molecules to not come together. Hence, this causes the ice to be less dense.
Rigby, S. (2021). Why does ice float on water?. Retrieved 25 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Ferlis Siah DFST/FT/2A04

2021-04-25 15:06:06 UTC

Generally, solids tend to be denser than their liquid forms. Ice, however, is an exception due to the hydrogen bonds that are present in the chemical structure of water. Negatively charged electrons are more attracted to the oxygen atom as compared to the hydrogen atoms, causing the oxygen atom to have a slight negative charge, while the hydrogen atoms have a slight positive charge.

While in liquid form, the hydrogen bonds are broken and formed continuously due to movement of the water molecules. When the water is frozen, a crystal latice structure would be formed. When the molecules want to form hydrogen bonds with the corresponding positive or negative charges, they will at the same time be repelled by the similarly charged atoms of the water molecule. This creates a slightly less dense structure, thus causing ice to have a lower density than water and allowing it to float.

Rigby, S. (2021). Why does ice float on water?. BBC Science Focus Magazine. Retrieved 25 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/.

Min Gin DFST/2A/05

2021-04-25 16:58:20 UTC

Ice is actually about 9% less dense than water, hence displacing water and hovering over it instead. Generally speaking, when a liquid is going through the process of freezing its molecules become more packed together, resulting in solids having a greater density than liquids. However for water, it consists of positively-charged and negatively-charged oxygen atoms. During the process of freezing, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart, preventing the ice from becoming any denser.

References:
Childrensmuseum, 2016. Why does ice float? | The Children's Museum of Indianapolis. Available from: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water [Accessed 26 April 2021]

victoria DFST/2A/04

2021-04-25 17:12:02 UTC

when ice freezes, it is about 9% less dense than water. this causes it to float on the ice surface. when temperature is lowered, the kinetic energy within the molecules is reduced. hydrogen bonds form extended networks between other molecules, which are constantly forming and breaking. at a certain temperature, the kinetic energy of the molecules fall below the energy of the hydrogen bonds. hence hydrogen bonds starts to form more quickly than they break, forming a crystal lattice structure which is less dense than the structure of liquid water.

Rigby, S. (2021) Why does ice float on water? Science Focus. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 26/4/21]

Caitlyn DFST/2A/04

2021-04-26 04:02:16 UTC

Ice is about 9% less dense than water. As the water is heavier, it displaces the lighter ice, causing the ice to float to the top. As a liquid is being cooled, more molecules are brought close together and need to be accommodated in a smaller area. This results in most solids having a greater density than liquids. However it does not apply to ice. Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When water cools, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart thus prevents the ice from becoming any denser.

References:
Childrensmuseum, 2016. Why does ice float? | The Children's Museum of Indianapolis. Available from: https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe it or not, ice,ice less dense than water?&text=So for water, the density,be less dense than water [Accessed 26 April 2021]

sean dfst/2A/03

2021-04-26 04:42:30 UTC

ice is about 9% less dense than water, which allows for the water to displace the ice and cause the ice to float to the top. ice is a deviation from the general rule that substances become denser as they cool down. this is due to the hydrogen bonding that occurs in water. water consists of positively charged hydrogen atoms and negatively charged oxygen atoms. once water cools down, it starts to form the crystal lattice structure, in which the same charges repel each other, preventing the molecules from getting too close. this results in a structure slightly less dense than water.

Rigby, S. (2021). Why does ice float on water?. Retrieved 26 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Ametis DFST 2A/04

2021-04-26 06:22:56 UTC

Ice floats in water because when water freezes into a solid form, the molecules can forn a stable hydrogen bonds locking into positions. Thus they cannot form as many hydrogen bonds, leading to the ice water molecules not being as close together as in liquid water hence reducing the density.
When ice becomes a solid, it will have a cage-like structure so there are many empty spaces between the particles. As the spaces are larger than compared to the spaces in between the molecules in liquid water. Thus the volume of ice is greater than that of water. Hence, the density is less than the density of water. Therefore, ice floats on water.

References:
Byjus.com. 2021. GDPR. [online] Available at: <https://byjus.com/questions/why-does-ice-floats-on-water/> [Accessed 26 April 2021].

Ying Jie dfst/2A/03

2021-04-26 06:22:58 UTC

When liquids are cooled, the molecules move closer to one another, resulting in an increase in density. Ice, however, is less dense than when it is a liquid. this is because water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. when water is cooled, hydrogen atoms move to separate the negatively-charged oxygen atoms, thus preventing the water from becoming denser. instead, when ice is formed, it becomes less dense than water, thus allowing ice to float on water.

Reference:
Blog. (n.d.). Retrieved April 26, 2021, from https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!

Andrea DFST/2A/03

2021-04-26 06:25:23 UTC

The texture of the tomato turned very watery and mushy after being thawed. This is because formation of ice crystals formed during freezing cause breakage of cell membranes hence it would become very watery after being thawed.

Extension.umn.edu.2018. The science of freezing foods. [online] Available at [https://extension.umn.edu/preserving-and-preparing/science-freezing-foods#:~:text=Fruits%20and%20vegetables%20that%20are,than%20it%20was%20when%20raw.] [ Accessed 25 Apr. 2021]

SHI HUI DFST/2A/03

2021-04-26 12:58:30 UTC

Liquids have a lower density than solids. The hydrogen bonds that form when water freezes into ice allow the molecules to be spaced farther apart, making them take more space, decreasing the overall density and making it float in the water. The water molecules in ice take up about 9% more space than liquid water, which means ice is about 9% less dense than water. When water freezes into its solid form, the molecules can form more stable hydrogen bonds, locking them into positions. As the molecules are not moving, they cannot form as many hydrogen bonds as other water molecules. This leads to ice water molecules not being as close together as in liquid water, thus reducing its density.

Reference:
Byju's.(2021). Why does ice floats on water? Available at: [Retrieved from: 26th April 2021].

Andrea DFST/2A/03

2021-04-26 13:45:46 UTC

This is because ice is about 9% less dense than water. Due to hydrogen bonding, the heavier water displaces the lighter ice causing it to float.
water molecules are held together by strong covalent bonds. the more electronegative oxygen atom better attract negatively-charged electrons compared to the hydrogen atoms. As a result, the electrons tend to hover closer to the oxygen atom hence oxygen atom have a partial negative charge while hydrogen atoms have a partial positive charge. the partial charges on the water molecules interact with each other. giving rise to hydrogen bond.

In liquid form, as the molecules move around, hydrogen bonds form and break and the molecules can slip past each other.

Anne Marie Helmenstine, P. D. (2020, February 3). Scientific Explanation of Why Ice Floats. ThoughtCo. https://www.thoughtco.com/why-does-ice-float-604304.

Kar Yee DFST/2A/03

2021-04-26 14:48:21 UTC

To determine whether the object floats or sinks, we have to look at its density. When an object has a smaller density than the liquid it is put in, it will float. This means that it displaces a weight of fluid equal to its own weight.

Although ice is a solid, it is roughly 9% less dense than water. When liquids are cooled, molecules are moved closer to one another hence most solids are usually denser than liquids. However, water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When it cools, the hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart, which prevents ice from becoming denser. Thus, density of ice decreases as temperature decreases.

Hence, following the theory mentioned above, ice will displace a weight equal to its own and hence can float on water.

Reference:
Byrd-McDevitt, L., 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Childrensmuseum.org. Available at: <https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!> [Accessed 26 April 2021].

Zheng Da DFST/2A/04

2021-04-26 14:54:15 UTC

Ice floats on water as it has a lower density than water. Density is a term to describe the relationship between the mass of matter and its volume or space it takes up. A water molecule is made up of one central oxygen atom attached to two hydrogen atoms. Each hydrogen atom of a water molecule has a slight negative charge which will be attracted to the slight positive charge of the oxygen atom of another water molecule, linking together to form a structure. In liquid water, these linkages are forming and being broken as the molecules move about, the empty spaces are being filled up. Whereas in the structure of ice, the molecules are held tightly in a fixed structure, many empty spaces are present. These empty spaces cause ice to float on water.

D'Augustino, T. Exploring our world: Why does ice float? Michigan State University. Available at: https://www.canr.msu.edu/news/exploring_our_world_why_does_ice_float. [Retrieved 26/4/2021]

Zhiying DFST/2A/03

zhiying20 — 2021-04-26 17:49:02 UTC

Upon freezing, the density of ice decreases by about 9 percent. This is because ice has a very different structure compared to liquid water in which the molecules align themselves in a regular lattice rather than more randomly as in the liquid form. This happens that the lattice arrangement allows water molecules to be more spread out than in a liquid, and, thus, ice is less dense than water.

Usgs.gov. 2021. Water Density. [online] Available at: [Accessed 26 April 2021].

Fiona DFST2A03

2021-04-27 01:19:55 UTC

Ice is less dense than water. Ice is the solid state of water which its water molecules held in fixed positions by the more stable hydrogen bonds formed between them. Whereas the molecules in liquid water can move more freely and are more spread out then those in ice. Thus, there are more molecules in per unit area of ice than in liquid water. Since p=m/v, ice is less dense than liquid water.

Motivans, E. (2017). The reason why ice floats. [online] ZME Science. Available at: https://www.zmescience.com/other/science-abc/reason-ice-floats/#:~:text=The%20reason%20why%20ice%20is%20less%20dense%20than [Accessed 27 Apr. 2021].

Lim Wei Ern DFST/2A/03

2021-04-27 03:45:31 UTC

When water is cooled and becomes ice, it forms a crystal lattice structure as the positively charged hydrogen atoms becomes more stable and has less pull on the negatively charged oxygen molecules hence, making ice about 9% less dense than water. Since ice is less dense than water, there will be an upward buoyant force applied on the ice, causing it to float on water.

Rigby, S. (2021). Why does ice float on water?. Retrieved 27 April 2021, from https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Cheng Jia-Lu DFST/2A/02

CJiaLu — 2021-04-27 04:13:38 UTC

Ice floats on water due to its difference in density. It is less dense than water due to the structure and organization of its molecules when frozen. The presence of hydrogen bonds between the water molecules form a rigid lattice structure that takes up 9% more space when froze, compared to liquid water. Hence, ice is able to float on water due to its lower density.

references: https://wonderopolis.org/wonder/why-does-ice-float-in-water
https://www.usgs.gov/special-topic/water-science-school/science/water-density?qt-science_center_objects=0#qt-science_center_objects

connie DFST2A02

2021-04-27 05:29:53 UTC

Ice floats on water because it is less dense than water. During freezing, stable hydrogen bonds are formed within the molecules, making them stationary in their positions. Their inability to move causes the molecules to be not as close to each other compared to water, hence decreasing the density of ice.

Why Does Ice Float on Water? (n.d.). Socratic Q&A. Retrieved on 27 April 2020, from https://socratic.org/questions/54bfd865581e2a7c49ba18c2

Xuan Ming DFST/2A/02

2021-04-27 07:49:00 UTC

Ice float on water because ice is denser than water. Water are made up of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When water cools to form ice, the hydrogen bonds adjust themselves to hold the negatively-charged oxygen atoms apart, which prevents the ice from becoming any denser. Thus ice floats on water as ice is denser than water, caused by the decrease in density of the water along with the decrease of temperature.

References:
https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!

Ngai Hang DFST/2A/01

2021-04-27 14:02:50 UTC

Ice floats on water due to the fact of density. Ice floats as its density is less than that of water. Archimedes’ principle says that the upward buoyant force pushing against the submerged object is equal to the weight of the displaced water. For something to float, the upward buoyant force must be at least as big as the force of gravity. A solid will float on a liquid if it is less dense. In the case of ice, oxygen atom pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites attract, the slight charges on different molecules interact with each other. In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other. However, as the water cools down, it starts to form into its crystal lattice structure. The result is a structure that is slightly less dense than liquid water.
References: https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Faith DFST/2A/02

2021-04-27 14:16:36 UTC

Water is heavier which displaces ice as ice is about 9% less dense than water. Water molecules are attracted to each other by weak hydrogen bond. They are formed between the positively-charged hydrogen atoms and negatively-charged oxygen atoms in the nearby water molecules. As the temperature decreases, the weak hydrogen bond holds the negatively-charged oxygen atom apart, forming a rigid structure called ice.

WONDEROPOLIS, n.d. Why Does Ice Float in Water?. [Online] Available at: https://wonderopolis.org/wonder/why-does-ice-float-in-water [Accessed 27 April 2021].

Wei Henn DFST2A02

2021-04-27 14:21:20 UTC

Ice floats on water because of the density difference. Water is 9% denser than ice. This is because when water decreases in temperature, the hydrogen bonds will adjust themselves to hold the negatively-charged oxygen atoms apart, stabilising the hydrogen bonds as the bonds are held in place when the water molecules are frozen. Since molecules can't move closely together like in water and are spread apart, density is lower than water.

references:
Doleki, K., 2015
Why Does Ice Float on Water? (n.d.). Socratic Q&A. [online]
Retrieved from: https://socratic.org/questions/54bfd865581e2a7c49ba18c2
(Accessed 27 april 2021)

Byrd-McDevitt, L., 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Childrensmuseum.org. Retrieved from: <https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!>
( accessed 27 april 2021)

2021-04-27 14:22:57 UTC

Kiefer Ng DFST/2A/01

2021-04-27 15:14:40 UTC

This is because ice is less dense than water. A water molecule is a molecule made up of one oxygen atom in the centre with a hydrogen atom on each side. The molecule is held together by covalent bonds.

The oxygen atom pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. As a result, the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites attract, the slight charges on different molecules interact with each other. These interactions are called hydrogen bonds

In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

Jing Yi DFST/2A/01

2021-04-27 15:22:09 UTC

Ice floats on water as ice is less dense than water. Ice is in solid form and molecules are able to form more stable hydrogen bonds with other water molecules and because of its fixed positions they are not able to form as many hydrogen bonds as when it is in liquid state and this leads to the molecules not being close together thus reducing its density.

Tricia Ling DFST/2A/01

2021-04-27 15:33:17 UTC

ice floats on water as it is 9% less dense than water. as water is heavier, it displaces the ice which is lighter and thus causes it to float up.
when a liquid is cooled, there are more molecules which are being brought closer together into a smaller area, thus resulting in most solids being denser than liquids. However, ice does not follow this as water consists of positively charged hydrogen and negatively charged oxygen atoms. the hydrogen atoms hold the oxygen atoms apart, preventing the ice from becoming denser thus causing it to float in water

References:
Blog. Why does ice float? | The Children's Museum of Indianapolis. (n.d.). https://www.childrensmuseum.org/blog/why-does-ice-float#:~:text=Believe%20it%20or%20not%2C%20ice,ice%20less%20dense%20than%20water%3F&text=So%20for%20water%2C%20the%20density,be%20less%20dense%20than%20water!

Glenda Lee DFST2A01

2021-04-27 21:18:32 UTC

Density is defined as mass per unit volume and any object that is less dense than water will float.

Density of Water: 1.0 gm/cubic cm
Density of Ice: 0.931 gm/cubic cm

Water has is a v-shaped molecule that is made up of an oxygen in the centre and a hydrogen atom on each side. It is held together by covalent bonds.

Since the oxygen atom pulls the negatively charged electrons more strongly than the hydrogen atoms, the elctrons will hover closer to the oxygen atom. This will result in the molecule having a slight negative charge around the oxygen end and a slight positive in the hydrogen ends.

Since opposites attract, there will be hydrogen bonds between the water molecules. In liquid form, as the molecules move around, hydrogen bonds will form and break over and over, and the molecules can slide past each other.

However, as the water freezes, it will start to form into a crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges will repel each other, creating empty spaces between its particle. And since density = mass/ volume, when the volume increases, the density will decrease. Thus, this results in ice being less dense than water.

Rigby, S. (2021). Why does ice float on water? Retrieved from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 27 April 2021].

Zakyyah DFST2A02

zakyyah — 2021-04-27 23:06:15 UTC

Water reaches maximum density at 4°C. As water freezes, it becomes less dense. This causes te ice to be displaced and float on top of the unfrozen water. Typically, most substances become more dense in their solid state. In the case of water, hydrogen bonding is present. Water is composed of one oxygen molecules covalently bonded to two other hydrogen atoms. The positively charged hydrogen is attracted to the negatively charged oxygen of a neighbouring water molecule via weak hydrogen bonding. As water cools to below 4°C, the hydrogen bonds alter to hold the negatively charged oxygen atoms apart, producing a crystal lattice.

References:
Helmenstine, A. (2020). Scientific Explanation of Why Ice Floats. ThoughtCo. Retrieved 27 April 2021, from https://www.thoughtco.com/why-does-ice-float-604304#:~:text=Ice%20floats%20because%20it%20is,ice%20floats%20to%20the%20top.

Yu Xuan DFST/2A/02

yxuannz — 2021-04-28 08:37:47 UTC

Ice is 9% less dense compared to water. Since water is heavier, the water molecules will then sink, causing the ice to float as it is lighter.

Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. When water cools down, the hydrogen bonds will adapt and hold the negatively-charged oxygen atoms apart, which prevents the ice to have higher density.

To sum up, the density of the water actually decreases along with a decrease in temperature which leads ice to be less dense than water.

References:
Childrensmuseum.org. n.d. Why does ice float? | The Children's Museum of Indianapolis. [online] Available at: [Accessed 28 April 2021].

Ber LIn DFST2A01

berlin201 — 2021-04-28 10:20:58 UTC

Ice floats on water because it is simply less dense than water.

Water in it's solid form (ice) is less dense than it's liquid form, which is an unusual property. This is due to the hydrogen bonding present in water molecules. Hydrogen bonding in water above 4 degrees Celsius break due to the kinetic energy being higher than that of the bonds. This constant movement causes there to be a a high amount of molecules sliding over one another or a higher density (mass/ unit vol). Once water starts to freeze completely at 0 degrees Celsius, it forms a solid with a crystal lattice structure (ice). with more even spacing between molecules it allows the ice to be able to float in water.

References:
Rigby. S (2021). Why does ice float on water [online]. Science focus. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/

TARA LIM DFST2A01

2021-04-28 11:17:41 UTC

Whether an object floats or sinks depends on the density. Ice is about 9% less dense compared to water and so it will float in water. Since water is heavier, it displaces the lighter ice, causing the ice to float to the top.

In water, as the molecules move around, hydrogen bonds form and break continuously, and the molecules can slide past each other. However, as the water cools down, it starts to form a crystal lattice structure. Water consists of positively-charged hydrogen atoms and negatively-charged oxygen atoms. The hydrogen bonds adjust to hold the negatively-charged oxygen atoms apart as water cools. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting too close. This prevents the ice from becoming any denser, resulting in a structure that is slightly less dense than liquid water. Hence, the density of water decreases along with a decrease in temperature causing ice to be less dense than water.

Byrd-McDevitt, L., 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Childrensmuseum.org. Available at: [Accessed 28 April 2021].

Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: [Accessed 28 April 2021].

Suvetha DFST2A01

2021-04-28 12:01:53 UTC

density decreases along with a decrease in temperature - causing ice to be less dense than water. Ice is about 9% less dense than water. Since the water is heavier, it displaces the lighter ice, causing the ice to float to the top.

Byrd-McDevitt, L., 2016. Why does ice float? | The Children's Museum of Indianapolis. [online] Childrensmuseum.org. Available at:<https://www.childrensmuseum.org/blog/why-does-ice-float> [Accessed 28 April 2021].

Yuan Ting DFST2A01

2021-04-28 12:46:53 UTC

Ice will float on water because it is less dense than compared to water. The presence of hydrogen bonding and with the molecules of water made up of slightly positively charged hydrogen and slightly negatively charged oxygen in a V-shape this allows the molecules to be able to move around and slip past one another as the hydrogen bonds present will continuously break and form. But when water starts to cool down, a crystal lattice structure will begin to form. Hydrogen bonds will not be formed between the positive and negatively charged as the same charges will repel and move apart. This then causes the ice to be slightly less dense than water allowing it to be able to float despite it being a solid.

References:
https://www.thoughtco.com/why-does-ice-float-604304#:~:text=Ice%20floats%20because%20it%20is,ice%20floats%20to%20the%20top
https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Nicholas Sng DFST1A01

2021-04-28 12:54:58 UTC

Ice floats on water as it is less dense than water. In water, molecules are able to move around which means that hydroge bonds form and break continuously and the molecules can slide past each other. As the water cools down, it forms a crystal lattice structure. When cooled to freezing temperature, hydrogen bonds adjust to hold negatively charged oxygen atoms apart as water cools. Thus preventing the molecules from moving around in solid ice form compared to liquid form and being less dense than liquid water.
References:
Rigby. S (2021). Why does ice float on water [online]. Science focus. Available from: https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Chantel Tan DFST2A01

2021-04-28 13:11:10 UTC

Any object that is less dense than water will float on water. The density of a substance can be defined as the relationship between the mass and the volume of the substance. The density of water is about 0.997g/cm³, while the density of ice is about 0.9168 g/cm³.

The oxygen atom in a water molecule pulls on the negatively charged electrons stronger than the hydrogen atoms can. Thus, the electrons tend to hover closer to the oxygen atom, leaving a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end. Since opposites attract, hydrogen bonds are present and the slight charges on different molecules interact with each other. In liquid form, as the molecules move around, the hydrogen bonds will form and break, allowing the molecules to slip past each other. However, as the water cools down, it starts to form into its crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same charges repel each other, stopping the molecules from getting too close. The result is a structure that is slightly less dense than liquid water.

References:

Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: [Accessed 28 April 2021].

Alethea Chua DFST2A01

2021-04-28 13:33:43 UTC

As water freezes into ice, it becomes less dense. Water reaches maximum density at 4°C. Although most substances are densest in solid/frozen state, water is an exception due to hydrogen bonding. One oxygen atom and two hydrogen atoms form a water molecule, which is held together by covalent bonds. Water molecules are often drawn to one another by weaker chemical bonds (hydrogen bonds) between adjacent water molecules' positively charged hydrogen atoms and negatively charged oxygen atoms. The hydrogen bonds change as the water cools below 4°C, keeping the negatively charged oxygen atoms apart. Since ice is around 9% less dense than liquid water, it floats. In other words, since ice takes up 9% more room than water, a liter of ice weighs less than a liter of water. The heavy water pushes the lighter ice to the surface, causing the ice to float to the top.

Rigby, S. (2021). Why does ice float on water? [online] BBC Science Focus Magazine. Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 28 Apr. 2021].

Amanda Ke DFST2A01

2021-04-28 14:25:14 UTC

Objects that are less dense than water are able to float thus, ice floats on water because it is less dense than water. Molecules in water are affected by hydrogen bonds. Oxygen atoms in water pulls on negatively charged electrons more than the hydrogens atoms, leaving the oxygen end with a slight negative charge and the hydrogen end with a slight positive charge. The interaction of the charges in different molecules are called hydrogen bonds. As water cools down, it starts to form into crystal lattice structure. While molecules with slight positive and negative charges want to form hydrogen bonds, it repels each other hence, stopping molecules from getting too close, resulting in its structure being less dense than liquid water. Therefore, ice floats on water.

Reference:
Rigby, S. (2021). Why does ice float on water? [online] BBC Science Focus Magazine. Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 28 April 2021]

jan DFST2A02

junjiexzx — 2021-04-28 14:27:16 UTC

ice floats on water because it is less dense than water. when water freezes and becomes ice, the molecules are able to form stable hydrogen bonds. these bonds are locked into position and are not able to form as many hydrogen bonds with other water molecules. this causes ice molecules to not be as close as compared to liquid water molecules, reducing its density.

Doleki, K., 2015
Why Does Ice Float on Water? (n.d.). Socratic Q&A. [online]
Retrieved from: https://socratic.org/questions/54bfd865581e2a7c49ba18c2
(Accessed 27 april 2021)

Tiffany Tang DFST/FT/2A/01

2021-04-28 15:08:38 UTC

Ice floats on water because ice is less dense than water.

A water molecule is made up of two hydrogen and one oxygen atoms. The slightly negative charge on the oxygen atom and the slightly positive charge on the hydrogen atoms attract other molecules so that the slight positive charges sticks to the slight negative; linking water molecules together forming a structure with many empty spaces. In liquid water, the links are forming and breaking over and over as the molecules move. In ice, solid water, the molecules are hardly moving, the links become more permanent and the spaces remain until the ice melts. If you look closely at an ice cube, you can see many tiny air bubbles trapped within the spaces.

Reference:
D'Augustino, T., 2016. Exploring our world: Why does ice float?. [online] MSU Extension. Available at: [Accessed 28 April 2021].

Anderson Tay DFST/FT/2A/02

2021-04-28 15:13:27 UTC

A substance floats if it is much less dense, or has much less mass per unit volume, than other elements in a mixture. For example, if you toss a handful of rocks into a bucket of water, the rocks, which are dense in contrast to the water, will sink. The water, which is much less dense than the rocks, will float. Basically, the rocks push the water out of the way or displace it. For an object to be capable to float, it has to displace a weight of fluid equal to its own weight.

Water reaches its most density at 4°C (40°F). As it cools in addition and freezes into ice, it sincerely becomes less dense. On the other hand, most components are most dense in their solid (frozen) nation than in their liquid state. Water is specific because of hydrogen bonding.

A water molecule is made from one oxygen atom and two hydrogen atoms strongly joined to every other with covalent bonds. Water molecules are additionally attracted to each different by way of weaker chemical bonds (hydrogen bonds) between the positively-charged hydrogen atoms and the negatively charged oxygen atoms of neighboring water molecules. As the water cools to beneath 4°C, the hydrogen bonds regulate to keep the negatively charged oxygen atoms apart. This produces a crystal lattice oftentimes regarded as ice.

Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% extra house than water, so a liter of ice weighs much less than liter water. The heavier water displaces the lighter ice, so ice floats to the top.

Helmenstine, A.M. (2020, February 3). Scientific explanation of why ice floats. Retrieved April 28, 2021, from https://www.thoughtco.com/why-does-ice-float-604304

Stella Loo DFST/FT/02

2021-04-28 16:47:21 UTC

When the temperature of water falls below 4 degree celsius, the kinetic energy of the water molecules < energy of hydrogen bonds. Hydrogen bonds form more frequently than they break, and the resulting ordered hexagonal structure is less dense than the disordered structure of liquid water. Since ice is less dense than water, ice will float on water.

Zaidan, G. and Morton, C., 2013. Why does ice float in water?. [online] TED-Ed. Available at: [Accessed 28 April 2021].

XinHui DFST2A02

2021-04-28 17:27:43 UTC

Ice floats as it is less dense than compared to water. When water is frozen, the molecules in the ice will form stable hydrogen bonds which are more spread out than in water where they are more densely packed.
In water, the molecules are constantly forming and breaking and the molecules will keep moving around in order fill up the empty spaces. However in ice, as the links are more permanent, the molecules do not move around as much and the spaces between the molecules remain.

Exploring our world: Why does ice float? (2016). Available at: https://www.canr.msu.edu/news/exploring_our_world_why_does_ice_float (Accessed: 28 April 2021).

Eunice DFST2A02

2021-04-28 19:53:47 UTC

Ice floats as it is less dense than water. The oxygen atom pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. As a result, the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.
Since opposites attract, the slight charges on different molecules interact with each other.
In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.
However, as the water cools down, it starts to form into its crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting too close. The result is a structure that is slightly less dense than liquid water.

Why does ice float on water? (2021)
Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 28 April 2021]

Yi Xian DFST2A02

2021-04-29 01:13:02 UTC

As known so far, solids are denser than liquids, but ice floats on water, meaning that ice is less dense than water.

Water has a density of 1.0 gm/cubic cm.
The density of ice Ih is 0.931 gm/cubic cm.

A water molecule is a V-shaped molecule made up of one oxygen atom in the centre with a hydrogen atom on each side. The molecule is held together by covalent bonds, which is when two atoms share a pair of electrons.

However, the oxygen atom pulls on these negatively-charged electrons much more strongly than the hydrogen atoms can. As a result, the electrons tend to hover closer to the oxygen atom than either of the hydrogen atoms. This leaves the molecule as a whole with a slight negative charge around the oxygen end, and a slight positive charge around the hydrogen end.

Since opposites attract, the slight charges on different molecules interact with each other. These interactions are called hydrogen bonds (which, technically speaking, aren’t bonds at all).

In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

However, as the water cools down, it starts to form into its crystal lattice structure. While the molecules want to form hydrogen bonds between the slight positive and negative charges, the same-charges repel each other, stopping the molecules from getting too close. The result is a structure that is slightly less dense than liquid water
Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 29 April 2021].
Molecules, W., 2021. Why does ice float?. [online] Worldofmolecules.com. Available at: https://www.worldofmolecules.com/3D/why-does-ice-float.html [Accessed 29 April 2021].

Muhammad DFST2A01

2021-04-29 02:06:44 UTC

At 4.4 degrees Celsius, water reaches its highest density. Water loses density when it cools and freezes due to the unique structure of hydrogen bonds. One oxygen atom is tightly bound to two hydrogen atoms with covalent bonds in each water molecule.

Weaker hydrogen bonds appear to attract water molecules to each other. In neighboring water molecules, these form between positively charged hydrogen atoms and negatively charged oxygen atoms.

As the temperature of water drops, weaker hydrogen bonds separate the negatively charged oxygen atoms, creating a rigid crystal honeycomb structure that we call ice. Ice molecules take up about 9% more space than liquid water molecules, implying that ice is about 9% less dense than water.

Why Does Ice Float in Water?. (2021). Retrieved 29 April 2021, from https://wonderopolis.org/wonder/why-does-ice-float-in-water

Ng Zhi En Christy DFST2A02

ngchristy09 — 2021-04-29 02:24:26 UTC

Ice floats on water because molecules in water are affected by hydrogen bonding.

A water molecule is a V-shaped molecule made up of one oxygen atom in the center followed by a hydrogen atom on each side. It is held together by covalent bonds.

In water, the hydrogen bonds can form and break multiple times while slipping past each other.

However, in ice, the oxygen atom pulls on these negatively-charged electrons more strongly than the hydrogen atoms can.
This causes the electrons to hover closer to the oxygen atom than either of the hydrogen atoms, leaving the molecule as a whole with a slight negative charge around the oxygen end, while a slight positive charge around the hydrogen end.

As the temperature cools, it starts to form into a crystal lattice structure. Despite the molecules wanting to form hydrogen bonds between the slight positive and negative charges, the molecules of the same-charges repel each other. Hence, stopping the molecules from getting too close and causing ice to be denser.

REFERENCES:
Rigby S. 2021. Why does ice float on water?

Available from:
https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 29th April 2021]

Ernest Tien dfst2a02

2021-04-29 02:30:06 UTC

ice floats on water due to the density gap between the two. Ice despite being a solid, has a lesser density compared to water, and this is because when water is becoming ice, the hydrogen atoms would keep the oxygen bonds in place which reduces the density further. since the lesser the density the easier it floats, ice floats on water.

Joe DFST2A02

2021-04-29 04:10:56 UTC

There is a small gap between between ice and water, where ice has a lower density than water. When the water slowly cools down and freezes. Hydrogen bonds will be formed, due to the hydrogen bonds not breaking due to the less active water molecules, there will be more hydrogen bonds. This ends up having a crystal lattice structure that is less dense than the very disordered liquid water. And when the density becomes lesser, it will float.
References:
Rigby, S., 2021. Why does ice float on water?. [online] BBC Science Focus Magazine. Available at: https://www.sciencefocus.com/science/why-does-ice-float-on-water/ [Accessed 29 April 2021].

Firzanah DFST01

firzanahhanifar2120 — 2021-04-29 04:25:08 UTC

Ice floats on water because it is less dense than water. However, it is uncommon for the solid form of substances to be less dense than its liquid form. Water is an exception because of its hydrogen bonding. Water molecules are held together by covalent bonds. the oxygen atom in water pulls strongly on the hydrogen atoms. the electrons then tend to hover closer to the oxygen atom than the hydrogen atom, leaving the molecule slightly negatively charged on the oxygen end and positively charged on the hydrogen end. when water freezes, it forms a crystal lattice structure and the like charges repel each other stopping the molecule from getting too close. this results in a structure less dense than liquid.

Titus DFST 2A01

2021-04-29 04:35:28 UTC

Ice floats on water because its density is lesser than the density of water. The density of water is about 0.997g/cm³, while the density of ice is about 0.9168 g/cm³.
In liquid form, as the molecules move around, hydrogen bonds form and break over and over, and the molecules can slip past each other.

Reference:
Rigby S. 2021. Why does ice float on water?

Available from:
https://www.sciencefocus.com/science/why-does-ice-float-on-water/

Ee Jay DFST2A01

2021-04-29 04:46:08 UTC

Ice has a lower density than water. The density of ice is 0.931gm/cubic cm while the density of water is 1.0gm/cubic cm. Ice molecules take up 9% more than water molecules as the weaker hydrogen bonds cause the negatively charged atoms to be separated. This causes the formation of a crystallized structure and the same charges will repel each other hence the molecules will not get too close. Resulting in a solid with a lower density.

Joanne Ng DFST 2A02

2021-04-29 05:16:57 UTC

Density of solid is usually higher than liquid state, in most cases. But not for ice.

Ice is 9% less dense than water. In liquid state, molecules slide around each other easily & hydrogen bonds form & break easily. However in solid state, molecules are arranged in a crystal lattice structure & molecules form more hydrogen bonds. These bonds are also more stable, causing molecules to be arranged in an orderly & packed manner. Therefore, ice density is lower than the water liquid density, causing it to float on water.

References:
Childrensmuseum.org. n.d. Why does ice float? | The Children's Museum of Indianapolis. [online] Available at: [Accessed 26 April 2021].
YouTube, 2013. Why does ice float in water? - George Zaidan and Charles Morton. [video] Available at: [Accessed 25 April 2021].