Revision guide - Crude oil

Question 1

What is a mixture?

Answer 1

It consists of two (or more) elements or compounds that aren’t chemically bonded to each other

Question 2

What is crude oil made of?

Answer 2

A mixture of hydrocarbons

Question 3

How does fractional distilation work?

Answer 3

It works continuously, with heated crude oil poper in at the bottom. The vapourised oil rises up the colmn and the various fractions are constantly tapped off at different levels when they condense

Question 4

What happens to the length of the hydrocarbon molecules change as you get down the tower?

Answer 4

AKA as the temperature gets higher for them to condense

Longer

Question 5

What are alkAnes? What are they made up of?

Answer 5

All the fractions of crude oils are hydrocarbons called alkanes

They are made up of chains of carbon atoms surrounded by hydrogen atoms

Question 6

Formula for alkanes?

Answer 6

Cn H2n+n

Question 7

Basic trends of alkanes?

Answer 7

• The shorter the oclecules, the more runny the hydrocarbon is - aka less viscous
• The shorter the molecule, the more volatile they are (turn into a gas at a lower temperature) - aka the lower the temperature at which the fraction vaporises and condenses - the lower its boiling point
• The shorter the molecule, the more flammable the hydrocarbon is

Question 8

Uses of crude oil?

Answer 8

• fuels - cars, boats, trains, planes
• Burned in central heating in homes
• In power statons to generate electricity
• Provides the raw materials for make various chemicals, including plastics

Question 9

Bad environmental things caused by crude oil?

Answer 9

• Oil spills - many animals poisoned
• You have to burn it, which causes things like acid rain, global warming/dimming