What characterizes a heterogeneous reaction?

A heterogeneous reaction is characterized by the presence of reactants that are in different phases. This means that at least one of the reactants is in a different physical state compared to the others, such as gas, liquid, or solid. For example, a common heterogeneous reaction might involve a solid catalyst interacting with gas reactants or a liquid reactant reacting with a solid.

This characteristic is significant because the interaction between different phases can lead to unique kinetics and mechanisms not present in homogeneous reactions, where all reactants are in the same phase. Understanding the phase of reactants in a heterogeneous reaction can be crucial for predicting how the reaction will proceed, the rates of reaction, and how to optimize conditions for desired outcomes.