Chemistry – Chemical reactions - Rate of reaction | e-Consult

Effect of Changing Pressure: Increasing the pressure of gaseous reactants generally increases the rate of reaction. This is because increasing the pressure effectively increases the concentration of the gaseous reactants.

Collision Theory Explanation: Collision theory dictates that reaction rates are dependent on the frequency of collisions between reactant particles. When the pressure of a gas increases, the volume decreases. This forces the gas particles closer together, resulting in a higher concentration of particles per unit volume. Consequently, the frequency of collisions between the gas particles increases. More frequent collisions lead to a higher probability of successful collisions, and therefore a faster rate of reaction. This effect is particularly pronounced for reactions involving gases. The rate of reaction is directly proportional to the partial pressure of the gaseous reactants.