Which of the following statement is not correct?

If concentration of reactants is increased by X times the rate constant K becomes e^{k /x}

The correct answer is option 1. If concentration of reactants is increased by X times the rate constant K becomes e^{k /x}.

Let us clarify each statement and explain why the incorrect statement stands out:

1. If concentration of reactants is increased by X times the rate constant K becomes \(e^{k /x}\):

This statement is incorrect. According to the rate law, if the concentration of reactants is multiplied by a factor of \( X \), the rate constant \( k \) changes by a factor of \( 1/X \), not \( e^{k/X} \). The rate law equation typically expresses the relationship as:

\(\text{Rate} = k [A]^m [B]^n\)

If both \( [A] \) and \( [B] \) are multiplied by \( X \):

\(\text{New Rate} = k \cdot X^m \cdot X^n = X^{m+n} \cdot \text{Rate}\)

Therefore, \( k \) would effectively change to \( k/X^{m+n} \), not \( e^{k/X} \).

2. Units of rate constant depend on order of a reaction:

This statement is correct. The units of the rate constant \( k \) depend on the overall reaction order. Different orders of reactions have different units for \( k \). For example:

For a first-order reaction (\( \text{rate} = k[A] \)), \( k \) has units of \( \text{time}^{-1} \).

For a second-order reaction (\( \text{rate} = k[A]^2 \)), \( k \) has units of \( \text{volume} \cdot \text{time}^{-1} \cdot \text{concentration}^{-1} \).

3. Order of a reaction can be deduced from experiment only:

This statement is correct. The order of a reaction cannot be determined solely from the stoichiometric coefficients in the balanced chemical equation. It requires experimental data where the rate of reaction is measured under varying concentrations of reactants to deduce the reaction order.

4. The overall rate of a reaction that takes place in different steps is determined by the slowest step:

This statement is generally correct. In a multi-step reaction mechanism, the rate-determining step (or slowest step) limits the overall rate of the reaction. However, it does not dictate the rate of each individual step; those can proceed at their own rates depending on their specific activation energies and concentrations.

Conclusion: The statement that is not correct among the options provided is: If concentration of reactants is increased by X times the rate constant K becomes\( e^{k /x}\)

This statement misrepresents how the rate constant \( k \) changes when the concentrations of reactants are altered in a chemical reaction scenario.