Obtaining Substances

Question 1

Why are hydrocarbons cracked?

Answer 1

To produce smaller, more useful molecules

Question 2

What happens when hydrocarbons are heated?

Answer 2

They vaporise

Question 3

Which 2 methods can crack vaporised hydrocarbons?

Answer 3

Passing over a hot catalyst, or mixing with steam and heated to a very high temperature so that thermal decomposition will occur

Question 4

What do the products of cracking include?

Answer 4

Alkanes and alkenes

Question 5

What are alkenes?

Answer 5

Unsaturated hydrocarbons (have double bonds)

Question 6

What happens when an alkene is reacted with bromine water?

Answer 6

It turns it from orange to colourless

Question 7

What are some of the products of cracking useful as?

Answer 7

Fuels