Concentration, Temperature, Catalyst — Prelims Questions

For a first-order reaction, the rate constant $k$ at $300 \text{ K}$ is $2.0 \times 10^{-2} \text{ s}^{-1}$. If the activation energy ($E_a$) for the reaction is $50 \text{ kJ/mol}$, what will be the approximate rate constant at $310 \text{ K}$? (Given: $R = 8.314 \text{ J mol}^{-1}\text{ K}^{-1}$, $\ln 2 \approx 0.693$)

Which of the following statements about a catalyst is INCORRECT?

For a reaction, the rate doubles when the concentration of reactant A is doubled, and the rate triples when the concentration of reactant B is tripled. What is the overall order of the reaction?

An increase in temperature from $293 \text{ K}$ to $313 \text{ K}$ for a reaction causes the rate constant to increase by a factor of 4. Calculate the activation energy ($E_a$) of the reaction. (Given: $R = 8.314 \text{ J mol}^{-1}\text{ K}^{-1}$, $\ln 4 \approx 1.386$)

Which of the following graphs correctly represents the effect of a catalyst on the energy profile of an exothermic reaction?

The rate of a reaction is given by Rate $= k[A]^2[B]^0$. If the concentration of A is tripled and the concentration of B is doubled, how many times will the rate of reaction increase?

According to the Boltzmann distribution curve, what happens to the fraction of molecules with energy greater than or equal to the activation energy ($E_a$) when the temperature is increased?