Topic 7: Organic Chemistry

Question 1

Addition polymerisation:

Answer 1

A reaction where many small molecules (monomers) join together to form very large molecules (polymers).

Question 2

Alcohols:

Answer 2

Alcohols contain the functional group –OH.

Question 3

What are the first 4 members of a homologous series of alcohols:

Answer 3

Methanol, ethanol, propanol and butanol.

Question 4

Alkanes:

Answer 4

Alkanes are the most common hydrocarbon found in crude oil. Alkanes have the general formula CnH2n+2

Question 5

Alkenes:

Answer 5

Alkenes are hydrocarbons with a double bond between two of the carbon atoms in their chain, causing them to be unsaturated. They have the general formula CnH2n

Question 6

Amino acids:

Answer 6

Amino acids have two different functional groups in a molecule. They react by condensation polymerisation to produce polypeptides.

Question 7

Carboxylic acids:

Answer 7

Carboxylic acids have the functional group –COOH.

Question 8

What are the first 4 in the homologous series of Carboxylic acids

Answer 8

Methanoic acid, ethanoic acid,
propanoic acid and butanoic acid.

Question 9

Catalytic cracking:

Answer 9

Long-chain hydrocarbons are heated to turn them into a gas. The vapour is then passed over a hot powdered aluminium oxide catalyst. The long chain molecules split apart on the surface of the catalyst.

Question 10

Combustion:

Answer 10

Combustion of hydrocarbon fuels releases energy. During combustion, the carbon and hydrogen in the fuels are oxidised.

Question 11

Complete combustion:

Answer 11

Water and carbon dioxide are the only products of the complete combustion of a hydrocarbon.

Question 12

Crude oil:

Answer 12

A finite resource found in rocks. It is the remains of an ancient biomass consisting mainly of plankton that was buried in mud. Most of the compounds in crude oil are hydrocarbons.

Question 13

Condensation polymerisation:

Answer 13

These reactions involve monomers with two functional groups. When these monomers react they join together and lose small molecules such as water.

Question 14

Cracking:

Answer 14

A process that involves breaking down larger hydrocarbons to produce smaller more useful molecules. Cracking can be done by catalytic cracking or steam cracking.

Question 15

DNA:

Answer 15

DNA encodes genetic instructions for the development and functioning of living organisms and viruses. Most DNA molecules are two polymer chains, made from four different nucleotides, in the form of a double helix.

Question 16

Esters:

Answer 16

The product of a condensation reaction between a carboxylic acid and alcohol. For
example: ethanol + ethanoic acid → ethyl ethanoate.

Question 17

Fermentation:

Answer 17

A chemical process by which molecules such as glucose are broken down anaerobically. Ethanol is produced when sugar solutions are fermented using yeast.

Question 18

Fractional distillation:

Answer 18

A method of separating a mixture of substances according to their different boiling points. Commonly used to separate crude oil into different fractions.

Question 19

Homologous series:

Answer 19

A series of compounds with the same functional group and similar chemical properties.

Question 20

Hydrocarbons:

Answer 20

Molecules that are made up of hydrogen and carbon atoms only.

Question 21

Nucleotides:

Answer 21

The monomers which make up DNA.

Question 22

Polyesters:

Answer 22

A category of polymers which contain the ester functional group in their main chain. Formed from condensation polymerisation.

Question 23

Polymers:

Answer 23

Large long-chain molecules made up of lots of small monomers joined together by covalent bonds.

Question 24

Polypeptide:

Answer 24

A chain of amino acids.

Question 25

Repeat unit:

Answer 25

The part of a polymer whose repetition would produce the complete polymer chain.

Question 26

Steam cracking:

Answer 26

Long-chain hydrocarbons are heated to turn them into a gas. The hydrocarbon vapour is then mixed with steam and heated to a very high temperature which caused them to split into smaller molecules.

Question 27

Path From fractional distillation to an Ester:

Answer 27

Crude oil – fractional distillation -> alkane – Cracking -> alkene – steam/hydration -> Alcohol – oxidising agent -> carboxylic acid – alcohol (condensation polymerisation) -> Ester