Order of a reaction : The sum of the powers of the concentration terms of the reactants present in the rate equation is called order of a reaction.
`to ` Order of a reaction can be `0,1,2,3,` and even a fraction
`{:(Eg: 1 N_(2)O_(5) to N_(2) O_(4) +1/2 O_(2)), (rate prop [N_(2) O_(5)]),(therefore " It is a first order reaction."):}|{:(2 2N_(2) O to 2N_(2)+ O_(2)),(rate prop [N_(2) O]^(2)),(therefore It is 2^(nd) "order reaction"):}`