The scientific method is a body of techniques for investigating phenomena, acquiring new knowledge, or correcting and integrating previous knowledge. To be termed scientific, a method of inquiry is commonly based on empirical or measurable evidence subject to specific principles of reasoning.

A hypothesis (plural hypotheses) is a proposed explanation for a phenomenon. For ahypothesis to be a scientific hypothesis, the scientific method requires that one can test it.

The control group is defined as the group in an experiment or study that does not receive treatment by the researchers and is then used as a benchmark to measure how the other tested subjects do.

Matter can change from one state to another if heated or cooled. If ice (a solid) is heated it changesto water (a liquid). This change is called MELTING. If water is heated, it changes to steam (a gas).

mass definition. In physics, the property of matter that measures its resistance to acceleration. Roughly, the mass of an object is a measure of the number of atoms in it. The basic unit of measurement for mass is the kilogram. (See Newton's laws of motion; compare weight.)

Volume is the quantity of three-dimensional space occupied by a liquid, solid, or gas. Common units used to express volume include liters, cubic meters, gallons, milliliters, teaspoons and ounces.

Weight is a force caused by gravity. The weight of an object is the gravitational force between the object and the Earth. The more mass the object has the greater its weight will be. Weight is a force, so it's measured in newtons.

Solid is one of the four fundamental states of matter (the others being liquid, gas, and plasma). It is characterized by structural rigidity and resistance to changes of shape or volume. ... Materials science is primarily concerned with the physical and chemical properties of solids.
a substance that flows freely but is of constant volume, having a consistency like that of water or oil.

A gas is a sample of matter that conforms to the shape of a container in which it is held and acquires a uniform density inside the container, even in the presence of gravity and regardless of the amount of substance in the container.
Evaporation is the process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure. Evaporation is a fundamental part of the water cycle and is constantly occurring throughout nature. 
Condensation is the process by which water vapor in the air is changed into liquid water. In other words, the water in the air, a gas known as water vapor, from your hot shower cooled when it met the surface of the cold mirror. This caused the water vapor to condense, or turn into its liquid form.
Freezing, or solidification, is a phase transition in which a liquid turns into a solid when its temperature is lowered below its freezing point. For most substances, themelting and freezing points are the same temperature; however, certain substances possess differing solid–liquid transition temperatures.

the positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass.
Electron cloud is an informal term in physics. It is used to describe where electrons are when they go around the nucleus of an atom.

BONDING. When atoms join together to form molecules, they are held together by chemical bonds. These bonds form as a result of the sharing or exchange of electrons between the atoms.

Variation in the number of electrons or neutrons does not change the type of element. Changing number of electrons produces ions while changing the number of neutrons produces isotopes. The modern periodic table is organized in order of increasing atomic number. The element's atomic mass in atomic mass units.

Eukaryotic cells contain membrane-bound organelles, such as the nucleus, while prokaryotic cells do not. Differences in cellular structure of prokaryotes andeukaryotes include the presence of mitochondria and chloroplasts, the cell wall, and the structure of chromosomal DNA.

Structurally, plant and animal cells are very similarbecause they are both eukaryotic cells. They both contain membrane-bound organelles such as the nucleus, mitochondria, endoplasmic reticulum, golgi apparatus, lysosomes, and peroxisomes. ... These structures include: chloroplasts, the cell wall, and vacuoles.

Organism. Organism: is an individual living thing, such as a plant, animal, bacterium, protest, or fungus. An organism has a body made up of smaller parts that work together. There are many different organisms.

Community, also called biological community, in biology, an interacting group of various species in a common location. For example, a forest of trees and undergrowth plants, inhabited by animals and rooted in soil containing bacteria and fungi, constitutes a biological community
A group of individuals of the same species occupying a particular geographic area.Populations may be relatively small and closed, as on an island or in a valley, or they may be more diffuse and without a clear boundary between them and a neighboring population of the same species.

Symbiosis is the ecological relationship between two or more organisms living closely together with some form of feeding relationship involved. The three mainsymbiotic relationships are: - Mutualism, where both organisms benefit. -Commensalism, where one organism benefits while the other organism is not harmed.

an organism, especially a soil bacterium, fungus, or invertebrate, that decomposes organic materials

◇ Herbivores that feed on green plants and detritivores that feed on decaying matter are called primary consumers. Carnivores that feed on herbivores or detritivores are called secondary consumers, while those that feed on other carnivores are called tertiary consumers. Compare producer.

Evaporation is the process of a substance in a liquid state changing to a gaseous state due to an increase in temperature and/or pressure. Evaporation is a fundamental part of the water cycle and is constantly occurring throughout nature.
Transpiration is the process by which moisture is carried through plants from roots to small pores on the underside of leaves, where it changes to vapor and is released to the atmosphere. Transpiration is essentially evaporation of water from plant leaves.
the draining away of water (or substances carried in it) from the surface of an area of land, a building or structure, etc.

wear away or change the appearance or texture of (something) by long exposure to the air.

SEDIMENT. Small, solid particles of material from rocks or organisms which are moved by water or wind, resulting in erosion and deposition. DEPOSITION. The process by which sediment settles out of the water or wind that is carrying it, and is deposited in a new location.

Physical weathering, also called mechanical weathering or disaggregation, is the class of processes that causes the disintegration of rocks without chemical change. The primary process in physical weathering is abrasion (the process by whichclasts and other particles are reduced in size).

the emission of energy as electromagnetic waves or as moving subatomic particles, especially high-energy particles that cause ionization.

Standard sea-level pressure, by definition, equals 760 mm (29.92 inches) of mercury, 14.70 pounds per square inch, 1,013.25 × 10 ³ dynes per square centimetre, 1,013.25 millibars, one standard atmosphere