What is a Catalyst?
A catalyst is a substance that increases the rate of a chemical reaction without undergoing any permanent chemical change itself. It participates in the reaction but is regenerated at the end, meaning it can be used repeatedly. Catalysts do not initiate reactions that wouldn't happen otherwise; they only speed up existing ones.
How Catalysts Work
Catalysts work by providing an alternative reaction pathway with a lower activation energy. Activation energy is the minimum energy required for a chemical reaction to occur. By lowering this barrier, more reactant molecules have sufficient energy to react at a given temperature, thus increasing the reaction rate.
Examples of Catalysts
A common industrial example is the use of platinum or rhodium in catalytic converters in cars, which convert harmful exhaust gases into less toxic substances. In biology, enzymes are biological catalysts that significantly accelerate biochemical reactions in living organisms, such as digestion and synthesis processes.
Importance and Applications
Catalysts are crucial in countless industrial processes, enabling more efficient and cost-effective production of plastics, fuels, pharmaceuticals, and many other chemicals. Their ability to accelerate reactions under milder conditions also contributes to energy savings and reduced environmental impact, making them vital for sustainable chemistry.