Which of the following statements is not correct about order of a reaction ?
(a) The order of a reaction can be fractional number
(b) Order of a reaction is experimentally determined quantity
(c) The order of reaction is always equal to the sum of the stoichiometric coefficients of reactants in the balanced chemical equation for a reaction
(d) The order of a reaction is the sum of the powers of molar concentration of the reactants in the rate law expression.
Answer: (c)
Order of Reaction
Order of reaction is equal to the sum of powers of concentration of the reactants in rate law expression.
For any chemical reaction
xA+yB→ProductRate=k[A]x[B]yOrder=x+y
Order of reaction can be a fraction also, Order of reaction is not always equal to the sum of the stoichiometric coefficients of reactants in the balanced chemical equation. For a reaction, it may or may not be the equal sum of the stoichiometric coefficient of reactants.
Hence, out of the given four statements, option (c) is not correct.