What is the molecularity of each of the following elementary reactions? Write the rate law for each. (a) 2 NO(g) → N₂O₂(g)

Key Concepts

Molecularity

Molecularity refers to the number of reactant molecules involved in an elementary reaction. It can be classified as unimolecular (one molecule), bimolecular (two molecules), or termolecular (three molecules). In the case of the reaction 2 NO(g) → N2O2(g), the molecularity is bimolecular because two NO molecules are involved in the reaction.

Rate Law

The rate law expresses the relationship between the rate of a chemical reaction and the concentration of its reactants. For elementary reactions, the rate law can be directly derived from the stoichiometry of the reaction. For the reaction 2 NO(g) → N2O2(g), the rate law is given by rate = k[NO]^2, where k is the rate constant and [NO] is the concentration of nitric oxide.

Elementary Reaction

An elementary reaction is a single step process in a chemical reaction mechanism where reactants are converted to products in one step. The rate of an elementary reaction is directly proportional to the concentrations of the reactants raised to the power of their coefficients in the balanced equation. Understanding elementary reactions is crucial for determining molecularity and writing accurate rate laws.