Chemical Kinetics — Prelims Questions

For a first-order reaction, the rate constant is $2.303 \times 10^{-2} \text{ s}^{-1}$. If the initial concentration of the reactant is $1.0 \text{ M}$, what will be its concentration after $100 \text{ seconds}$?

For a reaction $A + B \rightarrow \text{Products}$, the rate law is given as $\text{Rate} = k[A]^2[B]^1$. If the concentration of A is doubled and the concentration of B is halved, what will be the change in the reaction rate?

Which of the following statements is INCORRECT regarding a catalyst?

The half-life period of a first-order reaction is $60 \text{ minutes}$. What percentage of the reactant will remain after $240 \text{ minutes}$?

The rate constant of a reaction is $1.5 \times 10^{-3} \text{ s}^{-1}$ at $27^circ \text{C}$ and $3.0 \times 10^{-2} \text{ s}^{-1}$ at $77^circ \text{C}$. Calculate the activation energy ($E_a$) of the reaction. (Given: $R = 8.314 \text{ J mol}^{-1} \text{K}^{-1}$, $\ln 2 = 0.693$, $\ln 20 = 2.996$)

For a reaction, the plot of $\ln[A]$ versus time ($t$) gives a straight line with a negative slope. What is the order of the reaction and what does the slope represent?

For a reaction, the rate constant $k = 2.0 \times 10^{-2} \text{ L mol}^{-1} \text{ s}^{-1}$. What is the order of the reaction?