productsreactants

Products and reactants are fundamental concepts in chemistry describing the substances involved in chemical reactions. Reactants are the starting materials consumed during the reaction, while products are the new substances formed as a result.

In a chemical equation, reactants appear on the left of the arrow and products on the right. Coefficients indicate the relative amounts of each substance, reflecting the reaction's stoichiometry. The law of conservation of mass requires that the total number of atoms of each element is identical on both sides of the equation.

Many reactions are reversible, indicated by a double arrow. In such cases, reactants can form products and products can re-form reactants until equilibrium is reached. The position of this equilibrium depends on temperature, pressure, concentration, and other conditions.

Solvents and catalysts play auxiliary roles. The solvent provides the medium for the reaction and is not typically a reactant unless it participates. A catalyst increases the reaction rate without being consumed, leaving the overall stoichiometry unchanged.

Examples illustrate the distinction between reactants and products. Combustion of methane: CH4 + 2 O2 -> CO2 + 2 H2O. Ammonia synthesis: N2 + 3 H2 -> 2 NH3. Decomposition of hydrogen peroxide: 2 H2O2 -> 2 H2O + O2.

Note that the term "productsreactants" is not standard; the conventional terms are "reactants" and "products" used to describe the substances on each side of a chemical equation.