Final answer:
A catalyst increases the rate of a chemical reaction by lowering the activation energy required. It provides an alternative pathway for the reaction to occur, allowing it to happen at a faster rate and at lower temperatures. Catalysts are not consumed in the reaction and can be in different forms.
Step-by-step explanation:
A catalyst is a substance that increases the rate of a chemical reaction by providing an alternative pathway with lower activation energy, without being consumed in the process. It works by lowering the energy barrier, or activation energy, required for the reaction to occur. This allows the reaction to happen at a faster rate and at lower temperatures. For example, the catalytic converter in car exhaust systems contains a catalyst that converts harmful gases into less harmful substances.
Unlike increasing the temperature of a chemical reaction, which can speed up the reaction by providing more energy to the reactant molecules, a catalyst provides an alternative mechanism that requires less energy. This allows the reaction to proceed more quickly without increasing the temperature. Catalysts can be in various forms, such as solids, liquids, or gases, and they can be specific to certain types of reactions.
Learn more about How a catalyst works