Question

5. Define order and molecularity​

Answer 1

Explanation:

The order of reaction is an empirical quantity determined by experiment from the rate law of the reaction. It is the sum of the exponents in the rate law equation. Molecularity, on the other hand, is deduced from the mechanism of an elementary reaction, and is used only in context of an elementary reaction.

Answer 2

Answer:

Order of a Reaction : It is defined as the sum of the concentration terms on which the rate of a reaction depends as observed experimentally is called Order of Reaction .

Or

It is also defined as the sum of powers to which the concentration terms are raised in the rate law expression.

Molecularity : The number of atoms,ions or molecules that must collide with one another simultaneously so as to bring a chemical reaction .

Example : Decomposition of O2F2

O2F2 --------> O2 + F2

The molecularity is 1

Reaction is unimolecular.

Dissociation of HI

2HI ----> H2 +I2

Molecularity = 2

Reaction: Bimolecular.