Question

Which of the following statement is not correct?
(1) Molecularity of a reaction cannot be fractional/
(2) Molecularity of a reaction cannot be more than
three
(3) Molecularity of a reaction may or may not be
equal to the order of reaction
(4) Molecularity of a reaction is obtained from
balanced chemical equation
Please provide satisfactory explanation​

Answer 1

4) Molecularity of a reaction is obtained from balanced chemical equation

Explanation:

The probability that more than three molecules can collide and

react simultaneously is very small. Hence, reactions with the

molecularity three are very rare and slow to proceed.

It is, therefore, evident that complex reactions involving more than

three molecules in the stoichiometric equation must take place in more

than one step.

KClO3 + 6FeSO4 + 3H2SO4 → KCl + 3Fe2(SO4) 3 + 3H2O

This reaction which apparently seems to be of tenth order is actually

a second order reaction. This shows that this reaction takes place in

several steps.

Molecularity is obtained from balanced chemical equation of the slowest step which is the rate determining step.