5.13 I can describe the catalytic cracking of long chain hydrocarbons

1) define the term catalyst
A catalyst is a substance that changes the rate of a reaction (e.g. silica, liver, manganese dioxide) usually speeding it up but it can also slow down reactions like rust.

2)Why is a catalyst used?
It is used to speed up the reaction

3)why are high temperatures needed?
High temperatures are needed to break down the bonds of the long chain hydrocarbons and as a by product will also speed up the reaction.



NOTE: answers are in white colour

1)Why does liquid paraffin need to be broken down?
There is to many long chain molecules and not enough short chain molecules like kerosine which are more useful
2)What is the name of the process used to break down paraffin? Describe how it works.
Cracking- it involves the heating of long chain hydrocarbons with the influence of catalyst
3)How do you collect the gas produced?
You must collect under water as it is insoluble
4)What is the name of the catalyst used?
Ceramic catalyst - broken pot
5)What are the safety precautions of the experiment?

Do not let the water setback otherwise it turns into steam and can cause an explosion 

6)Why does the pot turn black?

It interacts with the inorganic molecules

7)What else is formed as a product of the experiment?

Smoky residue

8)Why is it important to keep heating?
If you stop the gas will start to cool and water may enter the apparatus through the bunsen valve