At equilibrium, the concentrations of the products and reactants will be constant but not equal. Kc is the equilibrium constant, expressing these equilibrium concentrations combined.

Equilibrium constants can be explained in terms of partial pressures of gases, Kp. It can be expressed from the equation for a reversible reaction.

Rate equations describe the rate of reaction in terms of concentration and order of the reaction with respect to each reactant. The rate constant k varies depending on the reaction.

The rate of a chemical reaction can be increased by increasing temperature, increasing reactant concentration, increasing the surface area of solid reactants or the use of catalysts. There are a number of ways we can determine the rate of reaction experimentally.

The rate constant for a reaction various with temperature and activation energy. This is shown by the Arrhenius equation.