Question

Define the order of reaction.

Answer 1

Order of a reaction: It is defined as sum of the powers to which the concentration (or pressure) terms are raised in the rate-law expression. The order of a reaction is an experimental quantity.

The order of a reaction, in general, may or may not be numerically equal to $a+b+c$ for a general reaction of type,

$Example:aA+bB+cC⟶lL+mM+pP$

Rate of reaction of this reaction is given by

Rate= $K\left[A{]}^x\right[B{]}^y[C{]}^z$

where, $x,y,z$ are order of reaction with respect to the reactants $A,B,C$.

Overall order of the reaction is given by $x+y+z$.