4.7🫐

Question 1

What is crude oil?
(Where it’s found) (where it’s from) (what it’s made up of)

Answer 1

An infinite resource found in rocks. It’s the remains of ancient biomass mainly consisting of plankton. It’s a mixture of 2 very large number of compounds such as hydrocarbons

Question 2

What is a hydrocarbon?

Answer 2

A molecule consisting of only hydrogen and carbon atoms

Question 3

What is an alkane?

Answer 3

Saturated compounds, single carbon bonded, general formula for the homologous series of alkanes is c(n)H(2n+2)

Question 4

What are the first 4 alkanes?

Answer 4

Methane, ethane, propane, butane

Question 5

How do you separate crude oil?

Answer 5

Physical processes such as fractional distillation

Question 6

What is the process of fractional distillation? (4 marker)

Answer 6

Crude oil enters the fractioning column and is heated up until the oil is vaporised which rises throughout the fractioning column depending on its boiling points and then condenses back into a liquid at the right fraction. The top is cooler, so hydrocarbons with lower boiling points rise towards the top and condense, hydrocarbons with high boiling points condense back into liquids at the bottom where it is hotter. Once they are liquified, they are tapped off for different uses.

Question 7

Why is fractional distillation used?

Answer 7

As it separated crude oil into many if the fur,s we use in our daily lives. Such as: petrol, diesel, kerosene and heavy fuel oil.

Question 8

What do the petrochemical industry produce.

Answer 8

Solvents, lubricants, polymers and detergents

Question 9

How are the vast array of natural and synthetic carbon compounds formed?

Answer 9

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

Question 10

What is the factor that affects properties of molecules?

Answer 10

The size of the molecules

Question 11

What are the 3 main properties of hydrocarbons?

Answer 11

Viscosity, flammability and boiling point

Question 12

What is the trend in viscosity?

Answer 12

Shorter molecule = less viscous (more runny)
Longer molecule = more viscous (less runny)

Question 13

What is the trend in flammability?

Answer 13

Shorter molecule = more flammable
Longer molecule = less flammable

Question 14

What is the trend in boiling points?

Answer 14

Shorter molecules = lower temp at which it is vaporised (lower boiling point)
Longer molecules = higher temp at which it is vaporised (higher boiling point)

Question 15

Why are hydrocarbons burnt?
What is this process?

Answer 15

So they can be used as fuel since the reaction produces energy. This is combustion

Question 16

What is the equation of hydrocarbon combustion?

Answer 16

Hydrocarbon -> carbon dioxide and water.

Question 17

What is oxidised in that reaction?

Answer 17

Hydrogen and carbon in the fuels are oxidised.

Question 18

What is cracking?

Answer 18

Long hydrocarbons can be cracked to produce smaller hydrocarbons that are in high demand.

Question 19

What are the 2 types of cracking?

Answer 19

Catalytic and steam

Question 20

What conditions are needed for catalytic cracking?

Answer 20

High temperature and a catalyst

Question 21

What conditions are needed for steam cracking?

Answer 21

Steam and a high temperature so that a thermal decomposition reaction can occur.

Question 22

What does cracking produce?

Answer 22

And alkane and an alkene

Question 23

Why is cracking used?

Answer 23

There is a higher demand for smaller molecules.

Question 24

What are alkenes also used to produce?

Answer 24

Alkenes are used to produce polymers and as starting materials for the production of many other chemicals