A product in science is a substance that is formed when two or more chemicals react. When a chemical reaction takes place, a new substance is often created from the atoms or molecules of the original substances. There are often multiple products formed in a reaction.
There are two types of substances in a chemical reaction. These are called the reactants and the products. Reactants exist before the chemical reaction, and are written on the left hand side of a scientific equation. The products are created during the reaction, and are written on the right hand side of the equation.
While the products of a reaction are new substances, the atoms that create them are the same as those in the reactants. A chemical reaction is just a way of re-arranging the atoms in a molecule to create a new substance.
There are many examples of chemical reactions in everyday life. Combustion, for example, is the chemical reaction that takes place in fire. This reaction combines certain types of high energy molecules with oxygen. The result is air and carbon dioxide, which are both called the products of the reaction.
Another example is photosynthesis, which takes place in plants. The reaction involves converting carbon dioxide into glucose and oxygen using sunlight. In this reaction, the products are the glucose and oxygen.