 What effect does a catalyst have on the rate of reaction? What I have here is hydrogen peroxide H2O2, and I'm going to put about 50 milliliters in each one of these containers Next I'm going to add some manganese dioxide in the first one and manganese dioxide is often used as a catalyst So let's see what happens to the rate at which this reaction occurs I'm going to stir it just a little, I'll do the same to the other If you look closely you can see little flakes of the manganese dioxide A catalyst lowers the activation energy but doesn't get consumed in the reaction So after the reaction is complete You can recover the catalyst and use it again