Crude Oil and Fuels

Question 1

What is viscosity?

Answer 1

How thick a substance is

Question 2

What is crude oil formed of?

Answer 2

The remains of ancient biomass that died millions of years ago. Mainly plankton

Question 3

What differentiates an alkane from an alkene?

Answer 3

Alkanes: have only single bonds in them.
Alkenes: have double bonds.

Question 4

What is the formula for an alkane?

Answer 4

CnH2n + 2

Question 5

How does the length of a hydrocarbon chain affect flammability?

Answer 5

Longer chain = lower flammability

Question 6

How does the length of a hydrocarbon chain affect boiling point?

Answer 6

Longer chain = higher boiling point

Question 7

How does the length of a hydrocarbon chain affect viscosity?

Answer 7

Longer chain = higher viscosity

Question 8

What is the first step of fractional distillation?

Answer 8

Crude oil is vapourised.

Question 9

What is the second step of fractional distillation?

Answer 9

The hydrocarbon gases enter the column.

Question 10

What is the third step of fractional distillation?

Answer 10

The hydrocarbon gases begin to rise up the column.

Question 11

What is the fourth step of fractional distillation?

Answer 11

As the hydrocarbon gases rise up the fractional distillation column, they cool down.

Question 12

How does temperature change as you go up a fractional distillation column?

Answer 12

Higher up the column -> cooler

Question 13

What happens when hydrocarbon gases in the fractional distillation column reach their boiling points?

Answer 13

They condense.

Question 14

What happens when gases in the fractional distillation column condense?

Answer 14

They become and a fraction and are collected.

Question 15

What is the temperature at the bottom of the fractional distillation column?

Answer 15

350°C

Question 16

What is the temperature at the top of the fractional distillation column?

Answer 16

50°C

Question 17

What is the structure of hydrocarbon molecules at the top of the fractional distillation column?

Answer 17

Short-chain hydrocarbons with low boiling points.

Question 18

From the top to bottom, name, in order, the fractions collected from a column.

Answer 18

1. Petroleum gas
2. Petrol
3. Kerosene
4. Diesel oil/gas oil
5. Residue (thick, sticky mixture of long-chain hydrocarbons used in making roads and flat roads)

Question 19

What fuels can be produced from fractional distillation?

Answer 19

Petrol, diesel oil, kerosene, heavy fuel oil, petroleum gases

Question 20

What is cracking?

Answer 20

The process of breaking up longer-chain hydrocarbons into smaller-chain ones.

Question 21

What does cracking produce?

Answer 21

Shorter-chain alkanes and alkenes.

Question 22

What two things can be used in cracking?

Answer 22

A zeolite catalyst, steam

Question 23

Why is cracking needed?

Answer 23

Shorter-chain hydrocarbons tend to be more useful so are in higher demand.

Question 24

What makes an alkene different from an alkane?

Answer 24

Alkenes have double bonds between carbons.

Question 25

What is the test for an alkene?

Answer 25

Bromine water. If an alkene is present, it turns from orange to colourless

Question 26

What effect do alkanes have on bromine water?

Answer 26

None.

Question 27

What is a fraction?

Answer 27

A group of hydrocarbons with similar chain lengths.

Question 28

What four useful materials can be produced from crude oil fractions?

Answer 28

Solvents, lubricants, polymers, detergents

Question 29

What are alkenes used for?

Answer 29

The formation of polymers.

Question 30

What is the reactivity of alkenes (compared to alkanes)?

Answer 30

Alkenes are much more reactive.