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Question
Define order of reaction. How does order of a reaction differ from molecularity for a complex reaction?
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Solution
Order of Reaction :
Rate = K[A]x [B]y
(x + y) = order of that chemical reaction.
The sum of powers of the concentration of the reactants in the rate law expression is called the order of that chemical reaction.
| Order of Reaction | Molecularity |
| Sum of power of the concentration of the reactants in the rate law expression | The number of reacting species (atoms, ions or molecules) taking part in an elementing reaction, which must colloide simultaneously in order to being about a chemical reaction. |
| Order is an experimental quantity It can be 0 or fraction. |
It cannot be zero or a non- integer |
| Order is applicable to elementary as well as complex reaction |
For complex reaction, molecularity has no meaning. |
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