Electrochemistry and chemical kinetics are formula-driven chapters where JEE often asks quick numericals. This set covers standard EMF, the Nernst equation, the link between E°, ΔG° and K, Faraday's laws and conductance, then rate laws, half-life and the Arrhenius equation. Take 2.303RT/F = 0.059 V at 298 K and F = 96500 C mol⁻¹.
How to practise: read each question and tap the option you think is correct. You will see right away whether you got it, along with a short explanation, and your score is tracked at the bottom of the screen. This set has 15 questions.
Topics covered in this set
- Standard electrode potentials and cell EMF
- Nernst equation and concentration effects
- E°, ΔG° and equilibrium constant
- Faraday's laws of electrolysis
- Conductance and Kohlrausch's law
- Rate law, half-life and Arrhenius equation
JEE Chemistry MCQs with answers and explanations
Q1. Given E°(Ag⁺/Ag) = +0.80 V and E°(Zn²⁺/Zn) = −0.76 V, what is the standard EMF of the cell Zn | Zn²⁺ || Ag⁺ | Ag?
a) −1.56 V
b) 0.04 V
c) 1.56 V
d) 0.80 V
Q2. For the Daniell cell Zn | Zn²⁺ (0.1 M) || Cu²⁺ (1 M) | Cu with E° = 1.10 V, what is the EMF at 298 K?
a) 1.16 V
b) 1.13 V
c) 1.07 V
d) 1.10 V
Q3. What is the potential of a hydrogen electrode (p(H₂) = 1 bar) dipped in a solution of pH 3 at 298 K?
a) +0.177 V
b) −0.177 V
c) 0 V
d) −0.059 V
Q4. What is ΔG° for a cell reaction with n = 2 and E°cell = 1.10 V?
a) −424.6 kJ mol⁻¹
b) −212.3 kJ mol⁻¹
c) +212.3 kJ mol⁻¹
d) −106.2 kJ mol⁻¹
Q5. A two-electron cell reaction has E°cell = 0.295 V at 298 K. What is its equilibrium constant?
a) 10²⁰
b) 10¹⁰
c) 10⁵
d) 10⁻¹⁰
Q6. A current of 2 A is passed through CuSO₄ solution for 965 s. What mass of copper is deposited? (Cu = 63.5)
a) 6.35 g
b) 0.635 g
c) 1.27 g
d) 0.3175 g
Q7. How many coulombs are needed to deposit 1 mol of aluminium from Al³⁺?
a) 193000 C
b) 289500 C
c) 32167 C
d) 96500 C
Q8. The conductivity of a 0.1 M solution of an electrolyte is 1.2 × 10⁻² S cm⁻¹. What is its molar conductivity?
a) 1200 S cm² mol⁻¹
b) 1.2 S cm² mol⁻¹
c) 120 S cm² mol⁻¹
d) 12 S cm² mol⁻¹
Q9. Given Λ°m(CH₃COONa) = 91, Λ°m(HCl) = 426 and Λ°m(NaCl) = 126 S cm² mol⁻¹, what is Λ°m(CH₃COOH)?
a) 391 S cm² mol⁻¹
b) 209 S cm² mol⁻¹
c) 643 S cm² mol⁻¹
d) 461 S cm² mol⁻¹
Q10. How does the molar conductivity of a weak electrolyte such as acetic acid change on dilution?
a) It increases sharply, especially at low concentration
b) It decreases sharply
c) It becomes zero
d) It stays constant
Q11. For the rate law rate = k[A]²[B], by what factor does the rate change when the concentrations of both A and B are doubled?
a) 4
b) 6
c) 8
d) 16
Q12. What are the units of the rate constant for a second-order reaction?
a) s⁻¹
b) L² mol⁻² s⁻¹
c) mol L⁻¹ s⁻¹
d) L mol⁻¹ s⁻¹
Q13. A first-order reaction has a half-life of 10 min. How long will it take for 87.5% of the reactant to be consumed?
a) 20 min
b) 30 min
c) 87.5 min
d) 40 min
Q14. The half-life of a zero-order reaction is:
a) 1/(k[A]₀)
b) [A]₀/2k
c) Independent of [A]₀
d) 0.693/k
Q15. The rate of a reaction doubles when the temperature rises from 300 K to 310 K. What is the approximate activation energy?
a) 26.8 kJ mol⁻¹
b) 107 kJ mol⁻¹
c) 5.4 kJ mol⁻¹
d) 53.6 kJ mol⁻¹
Quick revision notes
- E°cell = E°cathode − E°anode; Nernst: E = E° − (0.059/n) log Q.
- ΔG° = −nFE°; log K = nE°/0.059 at 298 K.
- Faraday: mass = (Q/F) × (M/n); 1 F = 96500 C.
- Λm = 1000κ/M; Kohlrausch gives Λ° of weak electrolytes.
- First order t½ = 0.693/k; zero order t½ = [A]₀/2k; Arrhenius k = Ae^(−Ea/RT).
Frequently asked questions
Are these JEE previous year questions?
No, they are original practice questions written to the JEE Main syllabus and level.
Why is 0.059 used in the Nernst equation?
At 298 K, 2.303RT/F = 2.303 × 8.314 × 298 / 96500 ≈ 0.059 V, which lets the equation use log base 10.
What is the difference between order and molecularity?
Order is found from experiment and can be zero or a fraction. Molecularity is the number of species in an elementary step and is always a whole number.
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