How do catalysts affect the rate of redox reactions?

Catalysts accelerate oxidation-reduction (redox) reactions by lowering the activation energy required for the process to occur, allowing the reaction to proceed at a faster rate.1

In the context of redox chemistry, catalysts function by entering into chemical combinations with reactants to form intermediates that react more readily to produce the desired end product. During this process, the catalyst is regenerated, meaning it is not consumed and can facilitate the transformation of many reactant molecules.21

Key aspects of how catalysts affect these reactions include:

• Rate Enhancement: Many redox reactions, such as the oxidation of organic compounds or the hydrogenation of molecules like nitrogen, are characteristically slow at ambient temperatures and pressures; catalysts enable these to occur at useful rates.3
• Selectivity: When multiple reactions are possible, a catalyst can selectively accelerate one specific redox pathway while excluding others.1
• Biological Redox: In living systems, specialized enzymes known as oxidoreductases catalyze the removal of electrons and hydrogen atoms, essential for metabolic processes.4
• Equilibrium: A catalyst does not change the position of the chemical equilibrium; it only increases the speed at which that equilibrium is attained.1