C7

Question 1

What is crude oil?

Answer 1

A finite resource found in rocks.
The remaining of ancient biomass made of plankton that was buried in mud.
Therefore, a mixture of a large number of compounds which are mostly hydrocarbons.

Question 2

What is a hydrocarbon?

Answer 2

A compound only containing hydrogen and carbon atoms.

Question 3

What is the general formula for an alkane?

Answer 3

CnH2n+2

Question 4

What is the name of an alkane containing 1 carbon atom?

Answer 4

Methane

Question 5

What is the name of an alkane containing 2 carbon atoms?

Answer 5

Ethane

Question 6

What is the name of an alkane containing 3 carbon atoms?

Answer 6

Propane

Question 7

What is the name of an alkane containing 4 carbon atoms?

Answer 7

Butane

Question 8

How can the hydrocarbons in crude oil be separated?

Answer 8

Fractional Distillation

Question 9

What uses do we have for the fractions of crude oil?

Answer 9

Fuels and the petrochemical industry

Question 10

What fuels are produced from crude oil?

Answer 10

Petrol, Diesel, Kerosene, Heavy Fuel Oil, Liquified Petroleum Gases

Question 11

What materials are produced by the petrochemical industry?

Answer 11

Solvents, lubricants, polymers, detergents

Question 12

Why are there lots of natural and synthetic carbon compounds?

Answer 12

The ability of carbon atoms to form families of similar compounds.

Question 13

What happens during fractional distillation?

Answer 13

The crude oil is heated and evaporates.

As the gas rises it cools and condenses at its boiling where it can then be collected.

Question 14

What properties of a hydrocarbon depend on its size?

Answer 14

Flammability, viscosity and boiling points

Question 15

What happens to the flammability of a hydrocarbon as it becomes larger?

Answer 15

Decreases

Question 16

What happens to the viscosity of a hydrocarbon as it becomes larger?

Answer 16

Increases

Question 17

What happens to the melting and boiling point of a hydrocarbon as it becomes larger?

Answer 17

Increases

Question 18

What happens during combustion of hydrocarbon fuels?

Answer 18

The carbon and hydrogen in the fuel are fully oxidized to make carbon dioxide and water.
This releases energy.

Question 19

What is the word equation for combustion of a fuel from crude oil?

Answer 19

Hydrocarbon + Oxygen  Carbon Dioxide + Water

Question 20

How can hydrocarbons be broken down into smaller molecules?

Answer 20

Cracking

Question 21

What happens during catalytic cracking?

Answer 21

The crude oil is vaporized and passed over a hot catalyst.

Question 22

What happens during steam cracking?

Answer 22

The crude oil is vaporized and mixed with steam and heated to a high temperature.

Question 23

What are the products of cracking?

Answer 23

Smaller useful alkanes and alkenes

Question 24

How can we test for alkenes?

Answer 24

Add bromine water and if the colour changes to clear, an alkene is present.

Question 25

What colour change happens when alkenes react with bromine?

Answer 25

The orange bromine water turns colourless.