* Change the equilibrium point of a reaction. A catalyst speeds up the rate of a reaction, but it doesn't affect the final equilibrium concentrations of reactants and products.

* Be consumed in the reaction. Catalysts are not used up in the reaction process. They facilitate the reaction but remain chemically unchanged.

* Affect the enthalpy change (ΔH) of a reaction. Catalysts only affect the rate of reaction, not the energy difference between reactants and products.

* Change the nature of the products. A catalyst cannot change the products of a reaction, only the rate at which they are formed.

In essence, a catalyst provides an alternative pathway for a reaction with a lower activation energy, allowing the reaction to proceed faster. It doesn't change the overall energetics of the reaction, nor does it become part of the reaction itself.