C6.2 Organic Chemistry (mocks Only)

Question 1

What’s the general formula for alkanes?

Answer 1

CnH2n+2

Question 2

What does unsaturated mean, in terms of bonds?

Answer 2

C=C double bond, only in alkenes

Question 3

Billy has two hydrocarbons, both are colourless. He wants to determine which hydrocarbon is an alkane, and which is an alkene. Describe an experiment where he can do so. (3 marks)

Answer 3

1. Add bromine water to hydrocarbons.
2. If alkene (unsaturated), solution will become colourless.
3. Else if alkane, solution will remain orange-brown.

Question 4

What is the suffix for the functional group -OH?

Answer 4

“-anol”

Question 5

Fractional distillation is used to separate what?

Answer 5

Crude oil.

Question 6

Outline the steps of fractional distillation. (5 marks)

Answer 6

1. Crude oil is added to fractionating column.
2. Column is is heated (along with crude oil). This means the column is hotter at the bottom and cooler at the top.
3. As the shorter chains have less bonds to break, and need less energy, they rise to the top as gases.
4. They (shorter chains) condense.
5. Shorter chains are collected at the top of the column, longer chains are collected at the top.

Question 7

What is cracking?

Answer 7

Cracking is the process of thermal decomposition used to extract shorter chains from longer chains.

Question 8

What is a hydrocarbon?

Answer 8

A hydrocarbon is a molecule containing ONLY hydrogen and carbon atoms.

Question 9

Why are shorter chains more useful?

Answer 9

They are more flammable, less viscous and have a lower boiling point.

Question 10

Name the two methods of producing ethanol.

Answer 10

Hydration

Fermentation

Question 11

General formula for alkenes.

Answer 11

CnH2n

Question 12

How many bonds can a single carbon atom form?

Answer 12

4 bonds.

Question 13

What type of reactions do alkenes take part in?

Answer 13

Addition reactions.

Question 14

Name the hydrocarbon: C3H7OH

Answer 14

Propanol