JEE Chemistry - MCQ Practice Questions

Half-life of a first-order reaction is 30 minutes. What fraction of reactant remains after 90 minutes?

The rate constant of a reaction increases from 4 × 10⁻³ s⁻¹ to 8 × 10⁻³ s⁻¹ when temperature increases from 300K to 310K. Calculate activation energy (R = 8.314 J/mol·K)

Which of the following statements about collision theory is INCORRECT?

For a zero-order reaction, the integrated rate law is [A] = [A]₀ - kt. If [A]₀ = 0.5 M and k = 0.02 M·s⁻¹, find time when [A] = 0

Consider the mechanism: (1) A + B ⇌ C (fast equilibrium), (2) C + D → E + F (slow). Which is the rate-determining step?

The rate law for a reaction is Rate = k[A]¹[B]⁰. If [B] is doubled and [A] is halved, how does the rate change?

At 25°C, the rate constant is 3 × 10⁻² s⁻¹ and at 35°C it is 6 × 10⁻² s⁻¹. What is the temperature coefficient (Q₁₀) for this reaction?

The decomposition of N₂O₅ is a first-order reaction. If 50% decomposes in 30 minutes, what is the rate constant?

In the reaction A → Products, doubling [A] increases rate by 4 times. The order of reaction is:

Which factor does NOT affect the rate constant k of a reaction?

For a reaction with Eₐ = 50 kJ/mol and A = 2 × 10¹³ s⁻¹ (Arrhenius pre-exponential factor), calculate k at 300K (R = 8.314 J/mol·K)

For an elementary reaction: 2A + B → Products, the rate law is:

Which statement about potential energy diagrams is CORRECT?

The integrated rate law for second-order reaction is 1/[A] = 1/[A]₀ + kt. If [A]₀ = 0.5 M, k = 0.4 M⁻¹s⁻¹, find [A] after 5 seconds

For the reaction: (1) Cl₂ ⇌ 2Cl (fast), (2) Cl + H₂ → HCl + H (slow), (3) H + Cl₂ → HCl + Cl (fast). The overall reaction is:

The half-life of a second-order reaction is 100 s when initial concentration is 0.5 M. What is the rate constant?

A reaction has Eₐ = 60 kJ/mol. How many times faster will it be at 327°C compared to 27°C? (R = 8.314 J/mol·K, assume A constant)