Thermal cracking and catalytic cracking of alkanes.

https://www.youtube.com/watch?v=Q3e-iB3QHFc

Whats a benefit of converting long chain hydrocarbons into shorter chain using cracking

Economical benefit , e.g for petrol / naphtha

Cracking also produces alkenes, they are reacting molecules , and are a major feedstock (raw material) for the chemical industry

What does thermal cracking require

Both a high temp (450 - 900 degrees) and pressure (70 atmospheres)

Whats a benefit of thermal cracking

We make a high percentage of alkenes in the products, alkenes are very useful molecules due to high reactivity

What happens during thermal cracking

A covalent bond between two carbon atoms splits to form intermediate molecules

When covalent bond splits, the intermediate molecules have one unpaired electron, these are called free radicals.

What does catalytic cracking require

A high temp (around 450 degrees), however does not require high pressure

Uses a zeolite catalyst, which contains a mixture of aluminium oxide and silicon dioxide.

Zeolite has a large surface area which helps to make it an effective catalyst.

What are products of catalytic cracking

Branched chain alkanes, they are especially useful for petrol, as they combust very easily

Catalytic cracking Can also produce cyclic alkanes and aromatic hydrocarbons such as benzene