When a chemical reaction takes place, one or more substances react to form one or more different substances. The reacting species are known as the reactants and the species that are produced are known as the products. By convention, reactants are listed on left side of an equation and products are listed on the right side. For example, if we consider the photosynthesis reaction, carbon dioxide and water react in the presence of sunlight to form glucose and oxygen, as per the following chemical equation:
`6CO_2 + 6H_2O + sunlight -> C_6H_12O_6 + 6O_2`
Here, the reactants (carbon dioxide and water) have been listed on the left side of the equation, while the products (glucose and oxygen) have been listed on the right side of the equation. We can similarly identify the reactants and products of any chemical reaction if we are provided with the reaction equation.
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