Answer:
Product.
Step-by-step explanation:
A chemical reaction may be defined as the reaction in which a new substance will form in the reaction. The evolution of gas, change in color during the reaction and evolution of heat determines the chemical reaction.
The substance that undergoes the chemical change is known as the reactant. The reactant that finally combines into the new substance known as product. The product is the final substance formed during the chemical reaction.
Thus, the answer is substrate.