Question

The number of molecules that react with each other in an elementary reaction is a measure of the :

• A. activation energy of the reaction
• B. stoichiometry of the reaction
• C. molecularity of the reaction
• D. order of the reaction

Hint:

For elementary reactions, molecularity directly corresponds to the rate law. For complex reactions, the rate law is determined experimentally.

Answer 1

The Correct Option is C

Molecularity refers to the number of reacting molecules in an elementary reaction.
It is an integer value and defines how many molecules or ions are involved in a single elementary reaction.
Option (1) activation energy refers to the energy required to start a reaction.
Option (2) stoichiometry refers to the ratio of reactants and products in a balanced reaction equation.
Option (4) order refers to the powers of the concentrations in the rate law, which may or may not be related to molecularity.
Hence, the correct answer is (3) molecularity.