Question

explain why a catalyst increases the rate of reaction but does not change the value of the equilibrium constant for that reaction 1990

Answer 1

Adding a catalyst makes absolutely no difference to the position of equilibrium, and Le Châtelier's principle does not apply. This is because a catalyst speeds up the forward and back reaction to the same extent and adding a catalyst does not affect the relative rates of the two reactions, it cannot affect the position of equilibrium.