Why can you use a variable amount of catalyst with silicone?


I’ve picked up some silicone for casting molds but am curious what effect the amount of catalyst I use will have on the finished mold.

In: Chemistry

By definition, a catalyst is something that speeds up a reaction without going through permanent change itself.

An example is the dissolved CO2 in coke will slowly turn into a gas and escape. A mentos provides a surface for this to escape faster. The mentos undergoes no chemical change in this reaction.

I am unfamiliar with the catalyst used in silicone, but I assume that it is only used to speed up the drying process. Adding less means it’ll still dry faster compared to having none, but adding too much means your final product will have too much catalyst left in it.