Which of the following statements are correct?

AThe order of a reaction can be fractional.
BThe molecularity of an elementary reaction is always a whole number.
CThe order of a reaction always equals the sum of the stoichiometric coefficients of the reactants.
DMolecularity can be assigned to the overall equation of any complex reaction.

Answer: A, B

Order is found experimentally and can be fractional (e.g.

3/2

), and molecularity of an elementary step counts colliding species so it is a whole number. Order need not equal the sum of coefficients for complex reactions, and a complex reaction has no single molecularity because it occurs in several steps.

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