fractional distillation

Question 1

what do you use fractional distillation to separate

Answer 1

crude oil

Question 2

what is crude oil made from

Answer 2

the remains of dead plants and animals

Question 3

how do you extract the crude oil from the rock

Answer 3

drilling and sucking the oil up to the surface

Question 4

Explain the process of fractional distillation

Answer 4

• crude oil is a mixture of hydrocarbons with different boiling points.
• The first step is to heat the crude oil to a very high temperature so that all of the compounds are evaporated from liquid to gas.
• The hot gaseous hydrocarbons then rise up the fractionating column (because hot gas rises).
• As they rise, they cool down, because the top of the column is cooler than the bottom.
• The hydrocarbons will condense when they become cooler than their boiling point, and the liquid hydrocarbons then collect in trays and drain out.
• The longer chain hydrocarbons condense at the bottom of the fractionating column because they have high boiling points.
• Meanwhile the shorter chain hydrocarbons condense at the top of the column because they have much lower boiling points.

Question 5

are short chain alkanes flammable or difficult to ignite

and what does this allow them to be used for?

Answer 5

very flammable

fuels

Question 6

what are long chain alkenes used for?

Answer 6

something else than fuels

or are broken down into smaller hydrocarbons by cracking

Question 7

what can petrochemicals (e.g butane) be used for expect from fuel?

Answer 7

feedstock
(raw materials for the petrochemical industry)

can be used to make:

• solvents
• lubricants
• polymers
• detergents

Question 8

define a feedstock

Answer 8

a raw material used to provide reactants for an industrial reaction.

Question 9

define a petrochemical

Answer 9

a substance made from crude oil, via chemical reactions.