Rate expression of a chemical change is $-\frac{dx}{dt}=\text{k}{\left[\text{A}\right]}^2\left[\text{B}\right]{\left[\text{C}\right]}^0$ .

The order of reaction is

For a chemical reaction , the rate expression is

$-\frac{dx}{dt}=\text{K}{\left[\text{A}\right]}^2\left[\text{B}\right]{\left[\text{C}\right]}^0$

$\text{Order of the reaction}=2+1=3$

Note: Order means the sum of powers raised over the reactant concentrations in the rate law of reaction.