NEET Chemistry Chemical Kinetics MCQs

For a reaction A + B → C, the rate law is found to be Rate = k[A]²[B]⁻¹. If the concentration of A is tripled while keeping the concentration of B constant, the factor by which the reaction rate changes is:

A reaction follows the rate law: Rate = k[A][B]². If the initial concentrations of both A and B are doubled, and the temperature remains constant, the initial rate of the reaction will increase by a factor of:

The half-life of a first-order reaction is 20 minutes. What fraction of the reactant remains after 80 minutes?

A reaction has a rate constant 'k' at temperature T₁ and k' at T₂ (T₂ > T₁). If the activation energy is Ea, which expression correctly relates k, k', T₁, and T₂ according to the Arrhenius equation?

A reaction between gases X and Y follows the rate law: Rate = k[X]²[Y]. If the concentration of X is tripled and the concentration of Y is halved, the new rate will be:

For a reaction with an activation energy ($E_a$) of 50 kJ/mol, how much would a 10°C increase in temperature increase the rate constant, according to the Arrhenius equation (assuming $ext{R} = 8.314 ext{ J mol}^{-1} ext{K}^{-1}$) at room temperature (approx. 300K)?

The hydrolysis of tert-butyl bromide in an aqueous medium follows the $S_N1$ mechanism. If the concentration of tert-butyl bromide is doubled, and the concentration of water is tripled, how will the rate of the reaction be affected?

A reaction $A + B \rightarrow C$ follows the rate law: Rate = $k[A]^{1/2}[B]^2$. If the concentrations of both A and B are halved, the rate of the reaction will become:

A reaction has a rate constant 'k' at temperature 'T'. If the temperature is increased by 10°C, the rate constant becomes '2k'. What is the activation energy ($E_a$) for the reaction (R = 8.314 J/mol K)?

A radioactive sample has a half-life of 10 days. What fraction of the original sample will remain after 20 days?