When we consider a balanced chemical equation of an elementary reaction which statement is applicable on it?
(A) Molecularity can never be zero
(B) Order is less than molecularity
(C) Order is equal to molecularity
(D) Order is greater than the molecularity
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → (A) and (C) only
Complete statement:
For an elementary reaction, molecularity can never be zero and order is equal to molecularity.
Reasoning:
(A) Molecularity can never be zero – True.
Molecularity is the number of reacting species colliding in an elementary step. It is always at least 1; it cannot be zero.
(B) Order is less than molecularity – False.
This may happen in complex reactions, but not necessarily true for elementary reactions.
(C) Order is equal to molecularity – True.
For an elementary reaction, the rate law follows the stoichiometric coefficients directly, so order = molecularity.
(D) Order is greater than molecularity – False.
This is not possible for an elementary reaction.
Hence, the correct option is (A) and (C) only.