CH2 - Hydrocarbons

They are drived from organisms that lived long ago

Include natural gas, petroleum and coal

Much of the worlds industrial and domestic energy needs are met by using them

They are available in a variety of forms, so the type of fuel can be matched with its use

They are all available at all times

They are non-renewable due to the fact that they are used up quicker than they are made

Combusion of them produces carbon dioxide, a greenhouse gas that absorbed infrared radiation and emits it in different directions

Acid rain as they many contain sulfur and on combustion this produces sulfur dioxide which reacts with water to make sulfuric(IV) acid which is oxidised to make sulfuric(VI) acid. Causes serious damage to buildings and health problems

Carbon monoxide formation 

The general formula of them is CnH2N+2

Each member of series differs from neighbour by CH2

They have similar chemical reactions as they're saturated

Physical properties may vary as molecular mass increases

They burn by reaction with oxygen, exothermic so they're used as fuels

Sufficient oxygen - complete combustion occurs, produces CO2 and H2O

Insufficient oxygen - incomplete combustion occurs, produces CO and H2O

It is the reaction between an organic compound and any halogen, also known as free radical substitution 

1) Initiation: UV light breaks bond between molecules and homolytic bond fission occurs to produce a radial

2) Propagation: Radical acts as a reactant, forming a radical as a product by a chain reaction

3) Termination: propagation steps continue until two radicals meet

Homologous series of unsaturated hydrocarbons

They contain a double bond with the general formula CnH2n

They are formed when petrouleum is cracked, generally used as fuels

They are much more reactive alkanes

They overlap sideways to produec a π bond, an area of high electron density

Alkenes have a pair of electrons in a π orbital, they are susceptible to attack by an electrophile (species that can accept a lone pair of electrons)

It involves heterolytic bond fission, leaving to an addition reaction

Mechanism uses curly arrows to show movement of a pair of electrons

Used as a test for an alkene

Bromine is brown and presence of an alkene is shown by decolorisation of bromine water

Hydrogenation

Catalysed by transition metals including platinum, palladium and nickel

Important as liquid vegetable oils can be made saturated by adding hydrogen to harden them to make solid edible fats

A carbocation is a carbon-containing positively charged ion

The joining of a very large number of monomer molecules to make a large polymer molecule

Addition polymerisation, the double bond is used to join the molecules, polymer doesn't contain a double bond but name is formed by adding poly to name of monomer so it involves ene

The section of the polymer that is repeated to make the whole structure

It is rigid and is used in food containers and general kitchen equipment

It can be used in water pipes, in waterproof clothing or as the insulating covering for electrical cable

It is hard and is used in many household items needing strength and rigidity

It can be made into an insulator and packing material by creating holes in the structure