Topic 6 - Organic Chemistry

Question 1

How are fossil fuels formed?

Answer 1

Fossil fuels are formed from dead plants and animals over millions of years under the action of heat and pressure.

Question 2

Give 5-10 examples of fossil fuels.

Answer 2

Natural gas
LPG
Petrol
Diesel
Paraffin
Candle wax
Peat
Lignite
Coal
Coke

Question 3

What does LPG stand for?

Answer 3

Liquified petroleum gas (LPG)

Question 4

Definition of a non-renewable resource

Answer 4

Non-renewable resources are those that cannot be replaced in a human lifetime and will eventually run out.

Question 5

Definition of a renewable resource

Answer 5

A renewable resource is one that can be replaced or replenished in a human lifetime.

Question 6

Example of a non-renewable resource

Answer 6

Fossils fuels

Question 7

Example of a renewable resource

Answer 7

Biomass

Question 8

What is the source for most hydrocarbons?

Answer 8

Crude Oil

Question 9

What is crude oil?

Answer 9

Crude oil is a black, viscous liquid and it is a mixture of hydrocarbons. Some of these hydrocarbons are solids and gases dissolved in the liquid.

Question 10

What is a hydrocarbon?

Answer 10

A hydrocarbon is a compound containing only carbon and hydrogen.

Question 11

What chemicals are obtained from crude oil?

Answer 11

Hydrocarbons

Question 12

What are the environmental implications of oil spillages?

Answer 12

Spillage of crude oil causes the following environmental problems:

• it destroys habitats
• it harms diving birds
• it creates eyesores on beaches and shorelines

Question 13

How is the separation of crude oil achieved?

Answer 13

Through fractional distillation

Question 14

Name 5-7 of the major hydrocarbons obtained from the fractional distillation of crude oil.

Answer 14

Refinery gas
Petrol
Naphtha
Kerosene
Diesel oil
Fuel oil and lubricating oil
Bitumen

Question 15

Definition of fractional distillation

Answer 15

Fractional distillation is the separation of crude oil into simpler mixtures of hydrocarbons called fractions.

Question 16

Fractional distillation is carried out in a …

Answer 16

Fractionating column

Question 17

The crude oil enters the bottom of the fractionating column at a temperature of …

Answer 17

450°C

Question 18

As you travel down the fractionating column (from top to bottom), we see an increase in the …

Answer 18

Boiling point of the fractions

Number of carbon atoms in the fraction

Size of the hydrocarbons

Question 19

The crude oil enters at the bottom of the fractionating column as …

Answer 19

A hot gaseous mixture

Question 20

How does the fractionating column allow gases to rise through the column?

Answer 20

The fractionating column has bubble caps, which allow gases to move upwards.

Question 21

The temperature _________ up the column

Answer 21

Decreases

Question 22

How are the fractions in crude oil separated within the fractionating column?

Answer 22

As the gases move up the column, hydrocarbons condense when the temperature of the column is the same as their boiling point.

Question 23

Give a use of refinery gas, one of the fractions of crude oil.

Answer 23

Bottled gas

Question 24

Give a use of petrol, one of the fractions of crude oil.

Answer 24

Vehicle fuel

Question 25

Give a use of naphtha, one of the fractions of crude oil.

Answer 25

Chemicals and plastics

Question 26

Give a use of kerosene, one of the fractions of crude oil.

Answer 26

Aircraft fuel

Question 27

Give a use of diesel oil, one of the fractions of crude oil.

Answer 27

Large vehicle fuel

Question 28

Give a use of fuel oil and lubricating oil, two of the fractions of crude oil.

Answer 28

Fuel for ships | Lubricants

Question 29

Give a use of bitumen, one of the fractions of crude oil.

Answer 29

Road tar

Question 30

Define a homologous series.

Answer 30

A homologous series is a family of organic compounds that have the same general formula, show similar chemical properties, show a gradation in their physical properties and differ by a CH2 unit.

Question 31

Name the four homologous series required for GCSE Chemistry.

Answer 31

Alkanes Alkenes Alcohols Carboxylic acids

Question 32

Of the four homologous series required for GCSE Chemistry, which two are hydrocarbons?

Answer 32

Alkanes | Alkenes

Question 33

Give the names of the first four Alkanes present in it's homologous series.

Answer 33

Methane Ethane Propane Butane

Question 34

Give the names of the first two Alkenes present in it's homologous series.

Answer 34

Ethene | Propene

Question 35

Give the names of the first two alcohols present in it's homologous series.

Answer 35

Methanol | Ethanol

Question 36

Give the names of the first two carboxylic acids present in it's homologous series.

Answer 36

Methanoic acid | Ethanoic acid

Question 37

Why are alcohols and carboxylic acids not described as hydrocarbons?

Answer 37

As they contain oxygen atoms as well as hydrogen and carbon atoms.

Question 38

What is the general formula for Alkanes?

Answer 38

CnH2n+2

Question 39

What is the general formula for Alkenes?

Answer 39

CnH2n

Question 40

What is the general formula for Alcohols?

Answer 40

CnH2n+1 OH

Question 41

What is the general formula for Carboxylic acids?

Answer 41

CnH2n+1 COOH

Question 42

For organic compounds containing one carbon atom, the prefix used is ...

Answer 42

Meth-

Question 43

For organic compounds containing two carbon atoms, the prefix used is ...

Answer 43

Eth-

Question 44

For organic compounds containing three carbon atoms, the prefix used is ...

Answer 44

Prop-

Question 45

For organic compounds containing four carbon atoms, the prefix used is ...

Answer 45

But-