Elephant toothpaste chemistry project

[Mohamad&Issa]

Hello...
I'm making elephant toothpaste for my chemistry project, where I'm using activated yeast+73 ml of water and soap+10 ml of hydrogen peroxide.But the reaction is very slow.What maybe the problem or if there any catalyst please help.
NOTE:after my search on internet I found that I should use 12% of hydrogen peroxide from the total volume of the solution(83ml).
Thanks

 

[Yanick]

Potassium iodide can be used instead of the yeast. I don't know any recipes off hand though.

You can try not mixing yeast with soap before hand. I'm not too sure but you might be screwing up the little buggers letting them sit in a surfactant solution. Also you can just use more yeast. Higher catalyst concentrations increase the rate of reaction. This can be the basis for a good science fair project if you can think of a way to measure how fast the reaction proceeds.

You should google this thoroughly, there will be plenty of recipes and procedures that you can try.

 

[eigenperson]

You are adding way too much water. You should really not put in any water at all (edit: except for the small amount required to keep the yeast happy).

Hydrogen peroxide is normally sold in low concentrations. Check your bottle; it is probably somewhere between 3% and 30%. If you have the strongest hydrogen peroxide that is normally available (30%), then adding over 7 times the volume of water is reducing the concentration to just 4%. In all likelihood you started with a much lower concentration of peroxide and ended up reducing the concentration to 1% or less.

This should fix the problem, but just in case it still doesn't work, try potassium iodide as a catalyst instead. It is a lot less finicky than yeast.