Chemical reactants that are in large lumps instead of small powder will take longer to react. Why is this?

A catalyst can also be used to speed up a reaction. Catalysts are not used up in the reaction. We saw manganese dioxide and liver catalyse the reaction when hydrogen peroxide breaks down into oxygen and water. What do we call catalysts in living organisms?

from left to right:boiled liver, manganese dioxide and fresh liver with hydrogen peroxide

We used ticker tape attached to trolleys to look at how the speed changed as the trolleys went down the runway.

 click for more results graphs
previous work : http://www.divshare.com/download/2029918-222

Discarded gum is a major headache for street cleaners

Gum splattered streets could soon be no more thanks to a virtually non-stick chewing gum that has been invented by UK scientists.

If it passes European health and safety tests, it could be in our shops by next year, the chemical company developing the gum says.

Revolymer claims its product is easier to remove from pavements, shoes and carpets than gums currently on sale.