Eventually it will not be strong enough to bleach your hair. Hydrogen peroxide does not last so long if you leave it out of the fridge or in the sunlight. The hairdresser's stock of hydrogen peroxide might last for several months if it was in the darkness in a fridge. However if someone added a pinch of manganese dioxide it would froth up and turn to water in a few minutes. The manganese dioxide has speeded up the breakdown of the hydrogen peroxide.
Enzymes are special cases of catalysts.
Now you must make your revision card. Manganese dioxide, platinum, enzymes on the second side. Add the card to your revision pack now. Tell the cat when you have understood and memorised this topic. Copyright 1999 - 2000 Gondar Design.