Having the same general formula, same functional group, differing from one member to the next by a -CH2- unit, sharing similar chemical properties, displaying a trend in physical properties.

Homologous series

A family of similar compounds with similar chemical properties due to the presence of the same functional group.

How does the boiling point change from the bottom to the top of the column

Decreases

How does the volatility change from the bottom to the top of the column

Increases

How does the chain length change from the bottom to the top of the column • Volatility • Boiling points • viscosity

Decreases

How does the viscosity change from the bottom to the top of the column

Decrease

Functional group

An atom or group of atoms that determine the chemical properties of a homologous series

Structural formula

An unambiguous description of the away atoms in a molecule are arranged e.g. CH2=CH2

Structural isomers

Compounds with the same molecular formula but different structural formula

Alkanes reactivity

Generally unreactive except with combustion and chlorine

General formula of alkanes

CnH2n+2

Saturated and example

Molecules in which all carbon-carbon bonds are single, alkanes

Unsaturated and example

Molecules with one or more carbon-carbon bonds that are not single bonds, alkenes

Complete combustion

Reacts with excess oxygen to produce CO2 and H2O

Incomplete combustion

Reacts with limited oxygen to produce either carbon monoxide and H2O or carbon and H2O

What happens in a substitution reaction

One atom or groups of atoms is replaced by another atom or group of atoms

General formula of alkenes

CnH2n

What kind of bonds do alkenes have

One or more carbon-carbon double covalent bonds.

How are alkenes formed

In the cracking of larger alkane molecules, hydrogen can form it as well but it needs high temp and catalyst

Reasons for cracking

Create more useful substances

Thermal cracking

High temperature and pressure

Catalytic cracking

Low temperature and pressure, catalyst

How to make alkanes from alkenes

React with hydrogen at 150C with nickel catalyst

Product of alkene and bromine water

Dibromoalkane

How is polyethene made

Alkenes can be used to make polymers by joining together in long chains, the product is called an addition polymer

How is ethanol made

By fermentation using aqueous glucose and yeast in the absence of oxygen at 25-35C

Word equation for fermentation

Glucose (enzymes) (in yeast) → ethanol + carbon dioxide

How is pure ethanol extracted

Fractional distillation

Apart from fermentation how else is ethanol made

Catalytic addition of steam to ethene using phosphoric acid as a catalyst 300oC and 60atm (6000kPa) pressure.

Ethanol with combustion/burn with oxygen

React in the same way as , complete combustion

General formula of alcohols

CnH2n+1OH

What is ethanol used for

Fuel and as a solvent

General formula for carboxylic acid

CnH2n+1COOH

Ethanoic acid reactions

Is a weak acid and will undergo reactions that other acids do with metals, carbonates and bases

Acid + metal

Salt + hydrogen

Acid + base

(neutralization) salt + water

Acid + carbonate

Salt + water + carbon dioxide

How is ethanoic acid formed

The oxidation of ethanol using bacterial oxidation during vinegar production or acidified potassium permanganate.

Carboxylic acid + alcohol

Will produce an ester, sulphuric acid acts as a catalyst and a dehydrating agent

Substitution reaction with chlorine and alkanes

Alkanes react with chlorine to form substituted alkanes in the presence of UV light proving the activation energy (photochemical reaction). This is a substitution reaction as a chlorine replaces one hydrogen.

Examples of natural polyimides

Proteins are polyimides formed from amino acids which is the monomer

What can be used to separate and identify amino acids

Chromatography

Draw the general structure of an amino acid

Ummmm yay

Environmental challenges caused by plastics

Disposal in land fill sites, accumulation in oceans, formation of toxic gases from burning

What are plastics made from

Polymers

Difference between addition polymers and condensation polymers

Addition polymers only have one product, condensation polymers have have 2 different monomers and water is removed

Draw and name the repeat polymer of this

Polypropene

Draw and name the repeat polymer of this

Polyvinyl chloride

Polymers

Large molecules built up from many smaller molecules called monomers

What is bad about plastics

Most plastics are not biodegradable and cannot be recycled so has implications for disposal

Producing an alcohol from alkenes and steam

Alkenes react with steam to produce an alcohol. This time it is the hydrogen and the hydroxide from water that adds across the double bond. An acid catalyst is needed, 300oC and 60atm (6000kPa) pressure

Formula equation for fermentation

C6H12O6 (aq) ————> 2C2H5OH (aq) + 2CO2(g) + 2ATP

Advantage of using fractional distillation to make ethanol

High purity, cheaper, easier access to resources

Disadvantage of using fractional distillation to make ethanol

Time consuming

Advantage of using fermentation to make ethanol

Better for the environment

Disadvantage of using fermentation to make ethanol

Lots of by products

Fractionating column

Refinery gas, gasoline, naptha, kerosene/paraffin, diesel oil/gas oil, fuel oil, lubricating oil, bitumen