By giving three examples explain that "the exponenets of the concentration terms are same or not as their stoichiometric coefficients in the balanced chemical reaction.

By giving three examples explain that "the exponenets of the concentra

1.	By giving three examples explain that "the exponenets of the concentration terms are same or not as their stoichiometric coefficients in the balanced chemical reaction.
Answer» Solution :In the following balanced equation the stoichiometric co-efficient are expressedas EXPONENTS of the concentration. Reaction (i)is the formation of `NO_(2)` `2NO_((g))+O_(2(g))to2NO_(2(g))` The differential form of this rate expression is given as Rate =`-(d[R])/(dt)=k[NO]^(2)[O_(2)]` The rate law is not theoretically but must be determined experimentally.So ,in the following reaction the VALUE of exponent is different and it is determined by experimental method. (i)Reaction:`CHCl_(3)+Cl_(2)toCCl_(4)+HCl` The differential form of this rate expression is Rate =`-(d[R])/(dt)=k[CHCl_(3)][Cl_(2)]^((1)/(2))` and `(1)/(2)` is exponent of `[Cl_(2)]` but it is not coefficient of `Cl_(2)` in reaction . (ii)Reaction :`CH_(3)COOC_(2)H_(5)+H_(2)OtoCH_(3)COOH+C_(2)H_(5)OH` In this reaction the rate expression is according on the base of experimental value as given Rate=`-(d[R])/(dt)=k[CH_(3)COOC_(2)H_(5)][H_(2)O]^(0)` Thus ,`H_(2)O` act as a reactant in reaction but experuimentally it is determined that the rate of reaction does not depenf on `[H_(2)O]` So ,rate law for any reaction cannot be predicted by merely looking at the balanced chemical equation i.e. theoretically but must be determined experimentally.