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(mainly compound that consist of two non-metals)

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1 )Concentrated sulfuric acid

(It cannot dry Ammonia as it will react with one another)

2) Quicklime

(It cannot dry Acidic gases as it will react with one another)

3) Fused calcium chloride

(It cannot dry Ammonia as it will react with one another)

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1)Evaporation to dryness is a method used to obtain a soluble solid from its solution

2)The solution is heated until all the water has evaporated

3)The soluble solid must to be stable to heat so that it will not decompose and must contain water of crystallisation .

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Sodium hydroxide dissociates in water to form sodium and hydroxide ions, Hydroxide ions will react with cations present.

NaOH(aq) --> Na+(aq) + OH-(aq)

Procedure:

1.Add a few drops of NaOH(aq) to sample solution

2.Observe for any changes(precipitation and effervescence)

3.Add NaOH(aq) in excess till no further change is observed

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Definition:

An acid is a substance which dissolves in water to give hydrogen ions (H⁺) as the only positive ions.

Acids are originally covalent molecules made up of molecules containing hydrogen atom(s) and other non-metal atoms. When added to water, the acid molecules dissociates (ionize) to form hydrogen ions and negative ions.

Strong Acid: Complete dissociation to produce high concentration of H⁺ ions.

Weak Acid: Partial dissociation to produce low concentration of H⁺ ions.

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Stronger, harder and less malleable than pure metal

Different atomic sizes disrupts the regular arrangement of metal layers hence unable to slide past each other easily

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1. Battery (short end is negative, long end is positive)

2. Electrolyte: Solution able to conduct electricity (using mobile ions)

The Electrolyte can be molten (melted state requiring high temperatures) or aqueous state (containing water and hence H⁺ ions and OH⁻ ions).

3. Electrodes:

Anode: Positive electrode where oxidation occurs

Cathode: Negative electorde where reduction occurs

(An Ox, Red Cat)

4. Electrodes can also be active or inert (refer to photo above)

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Decayed of plants and animals over the years mainly consists organic compounds

i.e(carbon ,hydrogen{hydrocarbon}

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General formula : (CnH2n+1 , n = 1)(anol)

Functional group : (-OH, Hydroxyl)

Note: It is mainly used as solvent for organic solute

Down the homologous series the melting and Boling points increases, decreasing flammability , more viscous, less volatile

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Definition:

A family of compound with the same general formula and have similar chemical properties (undergo the same chemical reactions) because they have the same functional group. Each member must differ from the next member by (CH₂) or 14 mr. There will be a gradual change in their physical change as you go down the homologous series.

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Functional Group:CnH2n+1OH

Suffix: -anol

E.g. Methanol, Ethanol, Propanol, Butanol, Pentanol, Hexanol, Heptanol, Octonol, Nonanol, Decanol.

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Oxidation: Acidified oxidising agents(eg.KMnO4 (Potassium manganate VII),K2Cr2O7(Potassium dichromate IV)

alcohol + oxidising agent -->carboxylic acid + water OR

alcohol + atmospheric oxygen ---> carboxylic acid and water

Combustion:C₂H₅OH + 3 O₂ → 2 CO₂ + 3 H₂O (l)(complete combustion) AND

C₂H₅OH + 2O₂ = 2CO +3 H₂O(incomplete combustion)

Esterification:CH₃COOH + C₂H₅OH ⇌ (conc.H₂SO4 )CH 3 COOC₂H 5 + H₂O

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A salt is an ionic compound formed when the hydrogen of the acid is being replaced with the metal ions from the reaction with metals, carbonates or bases, or ammonium ions from ammonium salts

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13.2 Molten Electrolyte, Inert Electrode

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13.2 Molten Electrolyte, Inert Electrode

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1. Possible Electrodes: Graphite/Platinum

2. In a molten electrolyte, ONLY ONE cation and anion are present.

3. Cations migrate to the cathode and is discharged without any competition. Similarly, the anion migrates to the anode and is oxidised.

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What is Electrolysis?

Electrolysis is the process where current is passed from an external source through an electrolyte to force a non-spontaneous redox reaction to occur.

Electroylsis occurs in an electrolytic cell

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13.3 Aqueous Electrolyte, Inert Electrode

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13.3 Aqueous Electrolyte, Inert Electrode

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In an aqueous solution, water is present and is able to form trace amounts of hydrogen ion (H⁺) and hydroxide ion (OH⁻)

H₂O ⇌ H⁺ + OH⁻

These negative and positive ions can compete with the other cations and anions present in the electrolyte, which leads to different products during discharge.

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13.4 Aqueous Electrolyte, Active Electrode (Part 1)

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13.4 Aqueous Electrolyte, Active Electrode (Part 1)

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Electrolytic cells containing active electrides may potentially take place in the reaction.

Typically, copper or Silver are used as Active Electrodes and can oxidise to form Copper(II) ions or silver ions.

This only occurs when they are placed at the anode, as only the anode undergoes oxidation.

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(Exam question picture above)

Answer:

Explanation:

Things to take note of:

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Ammonia dissociates partially in water to form ammonium and hydroxide ions, concentration of OH- ions is low

NH3(g) +H2O(l) <--> NH4+(aq)+OH-(aq)

Procedure:

1.Add a few drops of NH3(aq) to sample solution

2.Observe for any changes(precipitation and effervescence)

3.Add NH3(aq) in excess till no further change is observed

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1. Cations are positively (+) charged ions formed by metals except for NH4+(Ammonia)

2. Can be identified by two main alkaline reagents. NaOH(aq) and NH3(aq)

3. Identity can be deduced based on colour of precipitate(insoluble solid that emerges from a liquid solution) and whether is dissolves in excess of alkali

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1. Anions are negatively(-) charged ions formed by non-metals

2. Can be identified using 4 types of reagents:

Dilute Nitric Acid [HNO3(aq)]

Aqueous silver nitrate/nitric acid [Ag(NO3)2(aq)]

Aqueous barium nitrate/nitric acid [Ba(NO3)2(aq)]

Aqueous sodium hydroxide/aluminium foil [NaOH(aq)]

3. Identity can be deduced based on colour of precipitate and the gas given off

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Functional Group: CnH2n+1COOH

Suffix: -anoic acid

E.g. Methanoic Acic, Ethanoic Acid, Propanoic Acid, Butanoic Acid, Pentanoic Acid, Hexanoic Acid, Heptanoic Acid, Octanoic Acid, Nonanoic Acid, Decanoic Acid.

Carboxyl Group (minus H)

Suffix: -noate

E.g. Methanoate, Ethanoate, Propanoate, Buatanoate, Pentanoate, Hexanoate, Heptanoate, Ocatanoate, Nonanoate, Decanoate.

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(Exothermic)

CO₂+ H₂O + energy

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How to obtain Crude Oil from Fossil Fuels?

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How to obtain Crude Oil from Fossil Fuels?

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Fractional distillation

The light fraction is less viscous, burn more easily and have an decreased number of carbon atoms.

The heavier fraction is more viscous, burn less easily and have an increased number of carbon atoms.

Acronym:

PPNKDL

Pretty Princess Never Kiss Decent Looking Boys

Petroleum Petrol Naphta Kerosene Diesel Lubricating Oil Bitumen

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Sublimation is a phase transition process in which a substance transitions directly from a solid phase to a gas phase without passing through the intermediate liquid phase. In other words, sublimation occurs when a solid substance undergoes vaporization (conversion into a gas) at temperatures and pressures below its melting point.

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Rf = x/y x= distance between solvent and seperated components y = solvent font

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Paper chromatography is a type of chromatography technique used to separate and identify components in a mixture. It's based on the principle of differential partitioning between a mobile phase (solvent) and a stationary phase (the paper).

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Simple distillation is a technique used to separate components of a mixture based on differences in their boiling points. (Used when the boiling points of the substances are very far apart)

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A separating funnel is used for separating immiscible liquids or liquids with different densities.

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These resources are limited /finite resources, cannot be replaced quickly enough to keep up with the rate of use )

1)Natural gas (Methane,CH4): colourless, odourless

2)Crude oil / petroleum (mixture of fractions with different boiling points )

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90% of the crude oil is used as a fuel :

-To generate thermal energy and electricity

-Power motor vehicles and industrial activities

10% of the crude oil is used as petrochemical feedstock :

-Manufacture of plastics ,detergents ,medicines fertilisers, pesticides and synthetic rubber

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Biofuels (alternative renewable energy sources to crude oil and natural gas):

-Bioethanol-->Sugarcane

-Biogas-->Release of CH4 during food waste decomposition

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Source:

-Human: Incomplete combustion of fuels in car engines/fossil fuels 2C+O2-->2CO

Effects:

-It binds irreversibly with haemoglobin and prevents the transport of oxygen around the body; deprives the cells of oxygen, leading to suffocation or death

Preventive Measure:

-Use catalytic converters in vehicles to convert CO into CO2(less harmful)

2NO+2CO-->N2+CO2

2NO2+4CO-->N2+4CO2

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Acidic gas

Source:

-Natural: Volcanic Eruptions

-Human: combustion of sulfuric-containing fuels eg; coal (More important)

Effects:

-Living things: SO2 causes breathing difficulties due to irritation of respiratory system

-Environment: reacts with oxygen and moisture in the air to form sulfuric acid that dissolves in water to form acid rain

2SO2 + O2 + 2H2O --> 2H2SO4

Preventive Measure:

-Flue gas desulfurisation: Acidic exhaust can be treated with a wet mixture of calcium carbonate CaCO3 or calcium oxide CaOH2. Salt formed is harmless can be easily disposed.

CaCO3 + SO2 --> CaSO3 + CO2

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Acidic Gas

Source:

-Natural: Lightning activity

-Human: Internal combustion engines(at high temperatures, nitrogen in the air combines with oxygen in the air)

N2 + O2 --> NxOy

Effects:

-Living things: Oxides of nitrogen damage the lungs

-Environment: NO2 reacts with oxygen and moisture in the air to form nitric acid that dissolves in water to form acid rain

4NO2 + O2 + 2H2O --> 4HNO3

Preventive Measure:

-Catalytic convertors to convert oxides of nitrogen into nitrogen(harmless)

2NO2 + 4CO --> N2 + 4CO2

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Effects:

-Corrodes marble(limestone);marble leprosy and metal structures

-Acidifies soil and lakes/rivers, killing vegetation and aquatic life

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Do not spread

Edit with care

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Formula for the mole of substances (part l)

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Formula for the mole of substances (part l)

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E.g.

Combustion:

C₃H₈ (Propane) + O₂ -> CO₂ + H₂O

Step 1: x2 to C₃H₈

2C₃H8 +O₂ -> CO2 + H₂O

Step 2: Balance C

2C₃H8 +O₂ -> 6CO₂ + H₂O

Step 3: Balance H

2C₃H8 + O₂ -> 6CO₂ + 8H₂O

Step 4: Balance O

2C₃H8 + 10 O₂ -> 6CO₂ + 8H₂O

Step 5: LCM

C₃H8 + 5O₂ -> 3CO₂ + 4H₂O

:33

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Metallic bonding is the force of attraction between a 'sea' of mobile electrons and the nuclei of positively charged ions

Properties:

Malleable-ability to be hammered without breaking

Ductile-easily bendable without breaking

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Suffix: -ane

General Formula: (CnH2n+2), n greater or equals to 1

E.g. Methane, Ethane, Propane, Butane, Pentane, Hexane, Heptane, Octane, Nonane, Decane.

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Molecules are bonded by weak intermolecular forces/van der Waals forces

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Many atoms are bonded by strong covalent bonds throughout the structure

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Physical properties:

1) have a weak intermolecular forces of attraction between molecules

2) have a strong covalent bond within the molecule

3) As the no. of carbon atoms increase the melting and boiling points of the alkanes

4)As the molecular size increases ,the more viscous (harder for the solution to flow)

5) Alkanes are insoluble water but soluble in most organic solvents

6) As the molecular size increases ,their flammability decreases

Chemical properties:

1)Alkanes are generally unreactive because they consist of strong bonds like (C-C) ,(C-H),they are very hard to break.

2) Substitution with hydrogen (condition: UV light / sunlight )

3) Combustion

- complete combustion

CH4 (g)+2O2(g) --> CO2(g) +H₂O(g)

- incomplete combustion

C₄H10(g) +3O2(g)--> 2CO(g) + 3C(s) +5H₂O(g)

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Acids are only able to show their properties when dissolved in water.

Sour taste

Turns blue litmus paper red

pH less than 7

Turns universal indicator yellow, orange, or red. (depends on strength)

Able to conduct electricity

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Acid reaction 1: acid + metal —> salt + H2
Acid reaction 2: acid + CO32-(Carbonate) —> salt + H2O +CO2
Alkali reaction: alkali + ammonium salt —> salt + H20 +NH3
Neutralisation :acid + alkali —> salt + H2O

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Alkali is a base insoluble in water

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Explain in terms of bond breaking/making

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Explain in terms of bond breaking/making

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The energy absorbed in bond breaking bond of (products) is more/lesser than the energy released in bond forming in (reactants)

The energy  released in bond forming bond of (products) is more/lesser than the energy absorbed  in bond breaking in (reactants)

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There are free-moving electrons in graphite due to carbon atoms being bonded to 3 other atoms instead of 4, resulting in delocalised electron which acts as a charge carrier and conduct electricity

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Metal:
-Basic(React with acid)
Sodium Oxide
Magnesium Oxide
Copper Oxide
-Amphoteric(React with acid and base)
Zinc Oxide
Aluminium Oxide
Lead(II) Oxide

Non-metal:
-Neutral(Does not react)
Water
Carbon monoxide
Nitrogen monoxide
-Acidic(React with base)
Sulfur dioxide
Nitrogen dioxide
Sulfur trioxide

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Ammonia is colourless, irritant gas with a pungent, chocking smell; less dense than air 17 < 28

It has alkaline properties and is corrosive

It dissolves easily in water to form aqueous ammonia which turns litmus paper blue

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Ammonia is manufactured from nitrogen and hydrogen

Nitrogen is obtained through fractional distillation of liquid air

Hydrogen is obtained through cracking of petroleum

Exothermic reaction

Conditions:

250atm, 400-450 degrees Celsius and finely divided iron catalyst

N2(g)+3H2(g)--> 2NH3(g)

<--

High temperature; faster rate of reaction low yield

Low temperature; slower rate of reaction high yield

High pressure; faster rate of reaction too costly

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Ammonia:

Place moist red litmus paper at the mouth of the test tube

Moist red litmus paper turn blue

Chlorine:

Place moist blue litmus paper at the mouth of the test tube

Moist red litmus paper turn red than bleached white

Sulfur dioxide:

Place a piece of filter paper dipped in acidified potassium manganate(VII) at mouth of test tube

Purple acidified potassium manganate(VII) turn colourless

Carbon dioxide:

Pass gas evolved into limewater

White ppt formed

Oxygen:

Insert glowing splint into the test tube

Glowing splint is rekindled

Hydrogen:

Insert a lighted splint into the test tube

Lighted splint extinguished with a 'pop' sound

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Acronym: PSCMACZITLHCSG

Please-Potassium

Stop-Sodium

Calling-Calcium

Me-Magnesium ________________ React with water

A-Aluminium

Cute-Carbon

Zebra-Zinc

I-Iron ________________ React with steam

Totally-Tin

Love-Lead ____________ React with acid

Hot -Hydrogen

Curvy -Copper

Slavic-Silver

Girls-Gold

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1)Filtration is method used to separate insoluble solids from a liquid-solid mixture

2) large particles of the solid will be trapped by the pores of the filter paper while the smaller liquid particles pass through

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word formula :calcium ethanoate

molecular formular:(CH3COO)2Ca

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1. Concentration

-Increasing the concentration increase of reacting particles

-As such, the frequency of effective collision will increase between reacting particles

-Therefore, rate of reaction will increase with increasing concentration

2. Pressure

-Increasing pressure of gaseous particles increase the number of gaseous particles colliding with each other

-The frequency of effective collisions between gaseous reacting particles will increase

-Therefore, increasing pressure increase the speed of reaction

3. Surface area

-Decrease particle size result in larger surface are of reacting particles

-Hence, the frequency of effective collisions increases with larger surface area of reacting particles

-Therefore, smaller particle size increase speed of reaction

4. Temperature

-Increasing temperature increases the kinetic energy of reacting particles

-Increasing temperature increases the number of reacting particles with energy greater than or equal to Ea(Activation Energy)

-Therefore, the frequency of effective collisions increases for reacting particles

-Increasing temperature thereby increase rate of reaction

5. Catalyst

-Addition of catalyst will provide an alternative pathway with lower Ea (activation energy)

-More reacting particles will therefore have energy greater than or equal to Ea(activation energy)

-Therefore, the frequency of effective collisions will increase for reacting particles

-Addition of catalyst will increase rate of reaction (catalyst remain chemically unchanged)

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General formula ( CnH2n)

note : n must be 2 and above

functional group ( C=C ,Carbon-Carbon double bond)

Alkenes are unsaturated hydrocarbons ,meaning they are highly reactive.

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Physical properties:

1) have a weak intermolecular forces of attraction between molecules

2) have a strong covalent bond within the molecule

3) As the no. of carbon atoms increase the melting and boiling points of the alkenes

4)As the molecular size increases ,the more viscous (harder for the solution to flow)

5) Alkenes are insoluble water but soluble in most organic solvents

6) As the molecular size increases ,their flammability decreases

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Physical properties:

1) have a weak intermolecular forces of attraction between molecules

2) have a strong covalent bond within the molecule

3) As the no. of carbon atoms increase the melting and boiling points of the alkenes

4)As the molecular size increases ,the more viscous (harder for the solution to flow)

5) Alkenes are insoluble water but soluble in most organic solvents

6) As the molecular size increases ,their flammability decreases

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Combustion:C2H4 + 3O2 --> 2CO2 + 2H2O(complete combustion)

C2H4 + 2O2 --> 2CO + 2H2O(incomplete combustion)

Addition Reactions:

Hydrogenation:

Bromination:

Hydration:C2H4 + H2O --> C2H4OH(300 degree Celsius, 60 atm , Phosphoric (V)acid as a catalyst)(alkene to alcohol)

Addition polymerisation

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Definition : Cracking is the process in which larger hydrocarbons molecules , usually alkanes ,are broken down into smaller hydrocarbon molecules.

Conditions : 500o C - 700 o C, at 1 atmospheric pressure with aluminium oxide (Al₂O₃and silicon dioxide SiO2 )

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Used when the substances' boiling points are too close to one another and require more complex equipment to distill it .

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combustion

acid reaction

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How to get esters :

Alcohol + carboxylic acid --><-- ester + water(conditions are concentrated sulfuric acid, warm )

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Addition polymerisation :When unsaturated monomer join together without losing and molecules or atoms.

Condensation polymerisation :When monomers combine to form condensation polymers with removal of small molecules .E.g water molecules .

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Alkenes under high temperature and pressure the carbon = carbon will break and form bonds with the same monomer

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Amide linkage : dicarboxylic acid and a diamine

Ester linkage : dicarboxylic acid and diol

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plastic advantages :cheap ,easily moulded ,light, tough, waterproof, durable (resistant to decay ,rusting and chemical attack)

Disadavntages: land pollution, water pollution, air pollution

To mitigate the effects :

Physical methods:

Chemical methods:Cracking

Depolymerisation

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Redox involves reduction and oxidation, two chemical reactions occur simultaneously.

There are four definitions of reduction and oxidation

More than one definition may apply in a chemical reaction:

1. Oxidation

-> Gain of oxygen

-> Loss of hydrogen

-> Loss of electrons

-> Gain in oxidation state

2. Reduction

-> Loss of oxygen

-> Gain of hydrogen

-> Gain of electrons

-> Loss in oxidation state

3. Important things to note:

Oxidation and reduction can be written as half equations.

Each half equation requires state symbols and uses e⁻ to balance electrons on each side of the equation.

The chemical equation can be formed by combining both oxidation and reduction half equations.

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Crystallization exploits differences in the solubility of substances at different temperatures. By dissolving a substance in a suitable solvent at an elevated temperature and then cooling the solution, the solubility of the substance decreases, causing it to crystallize out of the solution.

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Higher temperature, Higher KE

Greater distance between particles, Greater PE

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Time: SI unit --> seconds(s)(Stopwatch)

Mass: SI unit --> kilogram (kg)(beam or electronic balance )

Temperature :SI unit --> degree celsius (°C ) or kelvin ( K ) (Thermometer)

Volume : SI unit --> cubic metre(m^3) (Beaker, Measuring cylinder ,pipette, burette)

Beaker-10

Measuring cylinder-10.0

Pipette-10.0

Burette-10.00

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It is held by strong electrostatic forces of attraction

(a compound that consist of a metal and non-metal)

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Net movement of particles from a region of higher concentration to a region of lower concentration

Faster in gases than in liquid due to higher kinetic energy

Affected by Mr and temperature; lower the Mr the faster they move; higher the temperature the faster they move

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(poly)ethene : used for clings wraps and plastic bags and toys .As it is very easy to mould it

polyamide :Nylon is normally used in clothing

polyester: Terylene is normally used in clothing ,curtain, parachutes ,fishing lines ,sleeping bags

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Downward delivery :

1. used to collect gases that is denser than air

2.gas will travel downwards as it is denser than air

E.g.(Carbon dioxide ,Chlorine gas )

Upward delivery :

1. used to collect gases that are less dense than air

2. gas will travel upwards as it is less dense than air

E.g.(Ammonia gas,Hydrogen gas )

Displacement of water :

1.Used for gases that are insoluble or slightly soluble in water

2. Gas is bubbled through water into a jar as the gas does not dissolves or only slightly dissolves in water

E.g.(Oxygen gas,Hydrogen gas,Carbon dioxide )

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Biofuel :

1) Biogas

it is produced during the decomposition of plants and animals

2) Bioethanol

made from sugarcane

have to be treated and fermented with yeast to produce bioethanol