Statement I: The overall order of the reaction is the sum of the exponents of all the reactants in the rate expression

Statement II: There are many higher-order reaction

Statement I and statement II are correct but statement II is not the correct explanation of statement I

The correct answer is: 2. Statement I and Statement II are both correct, but Statement II is not the correct explanation of Statement I.

Statement I: The overall order of the reaction is the sum of the exponents of all the reactants in the rate expression.
This statement is correct. In a rate expression, the exponents of the reactant concentrations represent the order of the reaction with respect to each reactant. The overall order of the reaction is obtained by summing up these individual exponents.

Statement II: There are many higher-order reactions.
This statement is also correct. Higher-order reactions exist, where the order of the reaction is greater than one. For example, a reaction with an overall order of 2 or 3 would be considered a higher-order reaction.

However, Statement II is not the correct explanation of Statement I. The correct explanation for Statement I is that the overall order of the reaction is determined by summing the exponents of the reactant concentrations in the rate expression.