Question

For a reaction A + B → products, the rate equation is given as rate = k[A]^1/2 [B]²

1. What is the order of the above reaction?

2. Distinguish between order and molecularity.

Answer 1

1. Order of the reaction = 2 + \(\frac{1}{2}\,=\,\frac{5}{2}\)

2. 

Molecularity	Order
1. Experimental	1. Theoretical
2. Can be zero	2. Can not be zero
3. Can be a fraction	3. Cannot be a fraction
4. No. of reacting species taking part in an elementary reaction, which must collide simultaneously to bring about a chemical reaction.	4. Sum of the powers of the concentration of the reactants in the rate law expression