It is neither, the reaction is the process.
The chemicals 'put in' to the reaction are called reactants, and those formed by the reaction are products
A substance that lowers the energy needed to start a chemical reaction is a catalyst.
The reactants
An endothermic reaction is one that consumes heat.
The reactant is the substance present at the start of a chemical reaction, while the product is the substance(s) formed from a chemical reaction.
energy
Combustion, burning, releases more heat that is taken in to start the reaction.
A substance that lowers the energy needed to start a chemical reaction is a catalyst.
The initial compounds in a chemical reaction are called reactants.
A chemical reaction need an activation energy to start.
centrioles
The reactants
The reactants
Either an energy source to start the reaction or a catalyst.
but
An endothermic reaction is one that consumes heat.
The substance present at the start of a chemical reaction is called a reactant. Reactants are the starting materials that undergo chemical changes to form products during a reaction.
The energy required to start a chemical reaction is called activation energy. It is the minimum amount of energy needed to initiate a reaction by breaking the chemical bonds of the reactants. This energy barrier must be overcome for the reaction to proceed.