Quantrex Quantrex AcademyJEE · NEET · NDA PYQs with solutions Open app
COMEDK2015ChemistryElectrochemistry

The cathode reaction in the dry cell will be

Options

  1. AZn (s) Zn ²⁺+2 e⁻
  2. BMnO ₂+ NH ₄⁺+e⁻⁻ MnO ( OH )+ NH ₃
  3. CZn ( Hg )+2 OH ⁻ ZnO (s)+ H ₂ O +2 e⁻
  4. DMnO ( OH )+ NH ₃ MnO ₂+ NH ₄⁺+2 e⁻

Correct answer

B. MnO ₂+ NH ₄⁺+e⁻⁻ MnO ( OH )+ NH ₃

Step-by-step solution

The cathode reaction in dry cell is MnO ₂+ NH ₄⁺+e⁻ MnO ( OH )+ NH ₃

Practice Electrochemistry on Quantrex Academy →

More from Electrochemistry

Which of the following is always true about a spontaneous cell reaction in a galvanic cell? 2026The G ^o for the reaction, Cd ²⁺(aq) + Zn (s) Zn ²⁺(aq) + Cd (s) is: [E^o_ Cd ²⁺/ Cd = -0.403, E^o_ Zn ²⁺/ Zn = -0.763 V ] 2026Resistance of 0.2 M solution of an electrolyte is 50 . The conductivity of the solution is 1.3 Sm ⁻¹ . If the resistance of 0.4 M solution of the same electrolyte is 260 , its mola 2026Using the data given below, the strongest reducing agent is: E^o_ Cr ₂ O ₇²⁻/ Cr ³⁺ = 1.33 V E^o_ MnO ₄^-/ Mn ²⁺ = 1.51 V E^o_ Cl ₂/ Cl ^- = 1.36 V E^o_ Cr ³⁺/ Cr = -0.74 V 2026The quantity of Ca that can be produced from molten CaCl₂ , with the same quantity of electricity (in coulombs) required to produce 4.8 g of Mg from molten MgCl₂ is: [Atomic mass o 20263.482 10⁻¹ g of Fe gets deposited when an aqueous solution of Ferric sulphate is electrolysed for 20 minutes using a current of "x" amperes. Find "x". (Atomic mass of Fe = 56amu). 2026Consider a Galvanic cell in which the following reactions occurs: Fe ²⁺(aq) + Ag ^+(aq) Fe ³⁺(aq) + Ag (s) . What is the standard potential of the cell? Given: E^0_ ( Ag ^+/ Ag ) = 2026What will be the change in the electrode potential of chromium electrode dipping into chromic sulphate solution, when the electrolyte is diluted 10 times at 25^ C? [ E^0 ( Cr ³⁺/ C 2026 Full Electrochemistry list All COMEDK PYQs