A chemical change can be speeded up by a catalyst
A catalyst can speed up a chemical reaction.
Chemical reactions are speeded up by enzymes (= proteins, = organic molecules) or more in general: by catalyst
it can be speeded up by a moist location.
the reaction for them is speeded up, and enhance performance as the speeded up reactions are carried out.
catalyst speeds up chemical change
It made it easier to communicate. It speeded up commerce and provided for greater business opportunities
when a chemical change occurs, chemical bonds are broken up
It is not a chemical change, unless you heat it sufficiently to make it catch fire.
The half life is practically a constant for each isotope; sometimes the half life depend on the chemical compound but the difference is very small.
Enzymes can speed up chemical reactions in the body by acting as biological catalysts. They lower the activation energy required for the reaction to occur, allowing it to proceed more quickly without being changed or consumed in the process.
It is not a chemical change because after cutting the chemical composition remain unchanged.
The decay of organic matter such as leaves is a chemical change.