A catalyst.
A substance that speeds up a chemical reaction is known as a CATALYST.
This is called reaction rate.
catalyst
a catalyst
speeds it up or starts it
The average rate of disappearance for a substance in a chemical reaction is the speed at which the substance is used up over time. It is calculated by dividing the change in concentration of the substance by the change in time.
catalyst-by lowering activation energy
This is a very vague question and would depend on the chemical that you are talking about. The easiest way I can think to explain it on a wide variety of chemicals is by using a catalyst (speeds up the process of a chemical reaction), or the use of an antagonist (Slows a chemical reaction). I hope this helps, but without any specific chemicals being named this is the best i can do. :) By heating we can change the rate of chemical change(reaction).
A substance that speeds up the rate of a chemical reaction without being consumed in the process is called a catalyst. Catalysts provide an alternative pathway with lower activation energy for the reaction to occur, increasing the reaction rate without being altered themselves.
A catalyst
A Catalyst enhances and speeds a chemical reaction without actually taking part in the reaction.
Substances that speed up the rate of reaction are called catalysts. Catalysts participate in chemical reaction but does not get consumed. Yeast is an example of biological catalyst.