Illustrated Glossary of Organic Chemistry

Product (reaction product): The endpoint of a chemical reaction or mechanism step. An entity within the reaction or mechanism step which is not a reactant, reagent, starting material, or substrate.

In this catalytic hydrogenation reaction, 1,2-dimethylcyclohexene is the starting material (or substrate), molecular hydrogen (H2) is a reactant, ethanol (CH3CH2OH) is the solvent, and platinum is a catalyst. The product is cis-1,2-dimethylcyclohexane.