Showing posts with label class12chemistry. Show all posts
Showing posts with label class12chemistry. Show all posts

Saturday, 8 November 2025

November 08, 2025

Calculate the e.m.f. of the following cell. Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe Given, E⁰(Cr³+/Cr) = -0.75V, E⁰(Fe²+ /Fe) = -0.45V

Calculate the EMF of the Cell: Cr | Cr³⁺ (0.1M) || Fe²⁺ (0.01M) | Fe

Electrochemistry numericals are an important part of Class 12 Chemistry. In this post, we will calculate the electromotive force (EMF) of the given electrochemical cell using standard electrode potentials and the Nernst equation.

Calculate the e.m.f. of the following cell.

Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe
Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V
Video solution:- 

Calculate the e.m.f. of the following cell.

Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe

Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V
Calculate the e.m.f. of the following cell.  Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe  Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V


Welcome to Electrochemistry Class XII Chemistry Hub — your one-stop destination for mastering one of the most important chapters in Class 12 Chemistry across all education boards (CBSE, ICSE, ISC, and State Boards).

Here, you’ll find comprehensive notes, concept explanations, important questions, and previous year questions (PYQs) carefully organized to help you score high in board exams. Our resources cover every key topic — from galvanic and electrolytic cells to electrode potentials, Nernst equation, and electrochemical series — with clear, step-by-step solutions.

Whether you’re preparing for school exams, board exams, or competitive tests (JEE, NEET), this website provides exam-oriented study materialpractice questions, and PYQ analysis to strengthen your understanding and boost your confidence.

✨ Key Features:

  • Detailed Electrochemistry notes for Class XII Chemistry (All Boards)
  • Important and Most Expected Board Questions
  • Chapter-wise Previous Year Questions (PYQs)
  • Concept-based MCQs and Numerical Practice
  • Easy-to-understand explanations for quick revision

Start your preparation today and make Electrochemistry your strongest chapter!

Questions:-

1.  Write the balanced half-reactions occurring at the anode and cathode of the galvanic cell:
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)


2. Represent the cell in which the following reaction takes place

Mg(s)+2Ag+ (0.0001M)||Mg²+ (0.130M) + 2Ag(s)

Calculate its E (cell) if  E⁰ (cell) = 3.17V .


3.Calculate the emf of the cell in which the following reaction takes place:
Ni(s) + 2Ag+ (0.002 M) → Ni²+ (0.160 M) + 2Ag(s)
Given that E⁰cell = 1.05 V


4. A copper-silver cell is set up in which the concentration of copper ion is 0.10 M and the concentration of silver ion is not known. The cell potential when measured was found to be 0.422 V. Calculate the concentration of silver ions in the cell. The given cell reaction is:

Cu +2Ag+ → Cu²+ + 2Ag

(Given E°(Ag+/Ag) = +0.80V, E°(Cu²+/Cu) = +0.34 V), use antilog (1.29) = 19.5



6.Write the Nernst equation and emf of the following cells at 298 K:

Mg(s) |Mg²+ (0.001M)||Cu²+ (0.0001 M)|Cu(s)


7.Write the Nernst equation and emf of the following cells at 298 K:
(ii) Fe(s)|Fe²+ (0.001M)||H+(1M)| H2(g)(1bar)| Pt(s)


8.Write the Nernst equation and emf of the following cells at 298 K:

Sn(s)|Sn²+ (0.050M)||H+(0.020M)| H2(g)(1bar)| Pt(s)


9. Write the Nernst equation and emf of the following cells at 298 K:

Pt(s) | Br-(0.010M)|Br2(l)||H+(0.030M)| H2(g)(1bar)/ Pt(s).


10.Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

                   2Cr(s)+3Cd²+ (aq)    →  2Cr³+ (aq) + 3Cd
Calculate the ΔG°  and equilibrium constant of the reactions.


11. Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

Calculate the ΔG°  and equilibrium constant of the reactions.


12. What is the amount of electricity required to deposite one mole of aluminium from a solution   of AlCl3 ?


13.  A solution of Ni(NO3)2 is electrolysed between platinum electrode using a current of 5A for 30mint. What is the mass of Ni deposited at the cathode. The atomic mass of Ni=58.5g(amu). 


14.What is amount of electricity required to deposit one mole of calcium from molten  CaCl2 ?


15. What is amount of electricity required to deposit one mole of Zinc from ZnSO4?


16. Consider the reaction Cr2O7²- + 14H+  + 6e-  2Cr2+   +  7H2O.  What is the quantity of electricity            in coulombs needed to reduce 1 mole of Cr2O72-  ? 


17.Calculate the mass of silver deposited from silver nitrate solution by a current of 2 ampere                 flowing for 30 minutes. (Equivalent mass of silver is 108).


18. How many hours does it take to reduce 3 mol of Fe3+ to Fe2+ with 2.00 A current? (1 Faraday = 96,500 C mol-¹, R = 8.314JK-1 mol-1 ) 


19. What mass of zinc can be produced by electrolysis of zinc sulphate solution when current of 1.5 Ampere is passed for 15 minutes ?The atomic Mass of Zinc = 65.4 amu. 


20. If a current of 0.5 ampere flows through a metallic wire for 2 hours, then howmany electrons would flow through the wire?


21. The molar conductance of infinite dilution for sodium acetate ( CH3COONa) Hydrochloric acid (HCI) and sodium chloride (NaCl) are 92.5, 426.9 and 120.4 S cm²mol-¹ respectively at 298 K. calculate the molar conductance of Acetic Acid (CH3COOH) at infinite dilution.


22.Calculate the molar conductance of a solution of MgCl2 at infinite dilution, given that molar ionic Conductance of ∧⁰ (Mg²+) = 126.1Scm²mol-¹ and ∧⁰(Cl) = 56.3 Scm²mol-¹


23. Calculte molar conductance at infinite dilution for acetic acid, given ∧⁰HCI=425ohm−¹cm²mol−¹,∧⁰ NaCI=188ohm−¹cm²mol−¹,∧⁰  CH3COONa=96ohm−¹cm²mol−¹ 


24.  Given molar conductivities at infinite dilution ∧⁰m for Ba(OH)2 = 517.6 Ω−¹cm²mol−¹ ∧⁰m for BaCl2 = 240.6 Ω−¹cm²mol−¹, ∧⁰m for NH4Cl =  129.8Ω−¹cm²mol−¹ . Calculate ∧⁰m for NH4OH


25. The resistance of 0.25 M molar solution of an electrolyte was found to be 75 Ω.Calculate molar conductivity of the solution, if the electrodes in the cell are 1.8 cm apart and have an area of cross section 3.6 cm². 


26. The Resistance of 0.5 M solution of an electrolyte was found to be 30 Ω. Calculate the molar conductivity of the solution if the electrodes in the cell are 1.5 cm apart and having area of cross section 2.0 cm². 


27. The electrical Resistance of a column of 0.05 M NaOH solution of diameter 1cm and length 50 cm is 5.55 × 10³ Ω. Calculate its Molar conductivity.


28. The Resistance of a 0.5 N solution of an electrolyte in a conductivity cell was found to be 25 Ω. Calculate the equivalent conductivity if the electrodes in the cell are 1.6 cm apart and having an area cross section 3.2 cm². 


29. Write equation and calculate e.m.f of cell at 298 K.

Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)

Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V



Cu (s)/ Cu²+ (0.130M) || Ag+ / Ag(s) (1.0×10-⁴M)
E⁰Cu+/Cu = 0.34 V, E⁰Ag+/Ag = 0.80 V
Given, F = 96500 C, R = 8.314 JK-1 mol-1
 


Mg (s) |Mg²+ (0.001M)||Cu²+ (0.0001M)|Cu (s)
Given E⁰ Mg²+ / Mg =-2.37V, E⁰ Cu²+ /Cu =0.34 V
 


33. Write the Nernst equation and calculate e.m.f of the following cell of 298 K.

Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)
Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V
 


Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
 


Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe
Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V


November 08, 2025

Write the nernst equation and Calculate the e.m.f of the cell of 298 K. Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s) Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V

This Class 12 Electrochemistry numerical helps students learn how to apply the Nernst equation to calculate the e.m.f. of a galvanic cell at 298 K. The given cell, Mg(s) | Mg²⁺ (0.130 M) || Ag⁺ (1.0×10⁻⁴ M) | Ag(s), uses standard electrode potentials E°(Ag⁺/Ag) = 0.80 V and E°(Mg²⁺/Mg) = –2.36 V. This numerical strengthens understanding of cell reactions, electrode potential, concentration effects and electrochemical concepts. Perfect for CBSE Class 12 board exam preparation, it helps students improve numerical solving skills and revise Electrochemistry with clarity. Ideal for notes, assignments and competitive exam practice.

Write the nernst equation and Calculate the e.m.f of the cell of 298 K.

Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
Video solution:- 

Write the nernst equation and Calculate the e.m.f of the cell of 298 K.
Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
Write the nernst equation and Calculate the e.m.f of the cell of 298 K.  Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s) Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V


Welcome to Electrochemistry Class XII Chemistry Hub — your one-stop destination for mastering one of the most important chapters in Class 12 Chemistry across all education boards (CBSE, ICSE, ISC, and State Boards).

Here, you’ll find comprehensive notes, concept explanations, important questions, and previous year questions (PYQs) carefully organized to help you score high in board exams. Our resources cover every key topic — from galvanic and electrolytic cells to electrode potentials, Nernst equation, and electrochemical series — with clear, step-by-step solutions.

Whether you’re preparing for school exams, board exams, or competitive tests (JEE, NEET), this website provides exam-oriented study materialpractice questions, and PYQ analysis to strengthen your understanding and boost your confidence.

✨ Key Features:

  • Detailed Electrochemistry notes for Class XII Chemistry (All Boards)
  • Important and Most Expected Board Questions
  • Chapter-wise Previous Year Questions (PYQs)
  • Concept-based MCQs and Numerical Practice
  • Easy-to-understand explanations for quick revision

Start your preparation today and make Electrochemistry your strongest chapter!

Questions:-

1.  Write the balanced half-reactions occurring at the anode and cathode of the galvanic cell:
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)


2. Represent the cell in which the following reaction takes place

Mg(s)+2Ag+ (0.0001M)||Mg²+ (0.130M) + 2Ag(s)

Calculate its E (cell) if  E⁰ (cell) = 3.17V .


3.Calculate the emf of the cell in which the following reaction takes place:
Ni(s) + 2Ag+ (0.002 M) → Ni²+ (0.160 M) + 2Ag(s)
Given that E⁰cell = 1.05 V


4. A copper-silver cell is set up in which the concentration of copper ion is 0.10 M and the concentration of silver ion is not known. The cell potential when measured was found to be 0.422 V. Calculate the concentration of silver ions in the cell. The given cell reaction is:

Cu +2Ag+ → Cu²+ + 2Ag

(Given E°(Ag+/Ag) = +0.80V, E°(Cu²+/Cu) = +0.34 V), use antilog (1.29) = 19.5



6.Write the Nernst equation and emf of the following cells at 298 K:

Mg(s) |Mg²+ (0.001M)||Cu²+ (0.0001 M)|Cu(s)


7.Write the Nernst equation and emf of the following cells at 298 K:
(ii) Fe(s)|Fe²+ (0.001M)||H+(1M)| H2(g)(1bar)| Pt(s)


8.Write the Nernst equation and emf of the following cells at 298 K:

Sn(s)|Sn²+ (0.050M)||H+(0.020M)| H2(g)(1bar)| Pt(s)


9. Write the Nernst equation and emf of the following cells at 298 K:

Pt(s) | Br-(0.010M)|Br2(l)||H+(0.030M)| H2(g)(1bar)/ Pt(s).


10.Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

                   2Cr(s)+3Cd²+ (aq)    →  2Cr³+ (aq) + 3Cd
Calculate the ΔG°  and equilibrium constant of the reactions.


11. Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

Calculate the ΔG°  and equilibrium constant of the reactions.


12. What is the amount of electricity required to deposite one mole of aluminium from a solution   of AlCl3 ?


13.  A solution of Ni(NO3)2 is electrolysed between platinum electrode using a current of 5A for 30mint. What is the mass of Ni deposited at the cathode. The atomic mass of Ni=58.5g(amu). 


14.What is amount of electricity required to deposit one mole of calcium from molten  CaCl2 ?


15. What is amount of electricity required to deposit one mole of Zinc from ZnSO4?


16. Consider the reaction Cr2O7²- + 14H+  + 6e-  2Cr2+   +  7H2O.  What is the quantity of electricity            in coulombs needed to reduce 1 mole of Cr2O72-  ? 


17.Calculate the mass of silver deposited from silver nitrate solution by a current of 2 ampere                 flowing for 30 minutes. (Equivalent mass of silver is 108).


18. How many hours does it take to reduce 3 mol of Fe3+ to Fe2+ with 2.00 A current? (1 Faraday = 96,500 C mol-¹, R = 8.314JK-1 mol-1 ) 


19. What mass of zinc can be produced by electrolysis of zinc sulphate solution when current of 1.5 Ampere is passed for 15 minutes ?The atomic Mass of Zinc = 65.4 amu. 


20. If a current of 0.5 ampere flows through a metallic wire for 2 hours, then howmany electrons would flow through the wire?


21. The molar conductance of infinite dilution for sodium acetate ( CH3COONa) Hydrochloric acid (HCI) and sodium chloride (NaCl) are 92.5, 426.9 and 120.4 S cm²mol-¹ respectively at 298 K. calculate the molar conductance of Acetic Acid (CH3COOH) at infinite dilution.


22.Calculate the molar conductance of a solution of MgCl2 at infinite dilution, given that molar ionic Conductance of ∧⁰ (Mg²+) = 126.1Scm²mol-¹ and ∧⁰(Cl) = 56.3 Scm²mol-¹


23. Calculte molar conductance at infinite dilution for acetic acid, given ∧⁰HCI=425ohm−¹cm²mol−¹,∧⁰ NaCI=188ohm−¹cm²mol−¹,∧⁰  CH3COONa=96ohm−¹cm²mol−¹ 


24.  Given molar conductivities at infinite dilution ∧⁰m for Ba(OH)2 = 517.6 Ω−¹cm²mol−¹ ∧⁰m for BaCl2 = 240.6 Ω−¹cm²mol−¹, ∧⁰m for NH4Cl =  129.8Ω−¹cm²mol−¹ . Calculate ∧⁰m for NH4OH


25. The resistance of 0.25 M molar solution of an electrolyte was found to be 75 Ω.Calculate molar conductivity of the solution, if the electrodes in the cell are 1.8 cm apart and have an area of cross section 3.6 cm². 


26. The Resistance of 0.5 M solution of an electrolyte was found to be 30 Ω. Calculate the molar conductivity of the solution if the electrodes in the cell are 1.5 cm apart and having area of cross section 2.0 cm². 


27. The electrical Resistance of a column of 0.05 M NaOH solution of diameter 1cm and length 50 cm is 5.55 × 10³ Ω. Calculate its Molar conductivity.


28. The Resistance of a 0.5 N solution of an electrolyte in a conductivity cell was found to be 25 Ω. Calculate the equivalent conductivity if the electrodes in the cell are 1.6 cm apart and having an area cross section 3.2 cm². 


29. Write equation and calculate e.m.f of cell at 298 K.

Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)

Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V



Cu (s)/ Cu²+ (0.130M) || Ag+ / Ag(s) (1.0×10-⁴M)
E⁰Cu+/Cu = 0.34 V, E⁰Ag+/Ag = 0.80 V
Given, F = 96500 C, R = 8.314 JK-1 mol-1
 


Mg (s) |Mg²+ (0.001M)||Cu²+ (0.0001M)|Cu (s)
Given E⁰ Mg²+ / Mg =-2.37V, E⁰ Cu²+ /Cu =0.34 V
 


33. Write the Nernst equation and calculate e.m.f of the following cell of 298 K.

Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)
Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V
 


Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
 


Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe
Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V
November 08, 2025

Write the Nernst equation and calculate e.m.f of the following cell of 298 K. Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M) Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V

 This Class 12 Electrochemistry numerical explains how to use the Nernst equation to calculate the e.m.f. of the Ni‖Cu cell at 298 K. The cell consists of Ni | Ni²⁺ (0.01 M) || Cu²⁺ (0.01 M) | Cu, with standard electrode potentials E°(Cu²⁺/Cu) = 0.34 V and E°(Ni²⁺/Ni) = –0.22 V. Students learn to identify the anode, cathode, write cell reactions, and apply the Nernst equation for equal ion concentrations. This numerical strengthens board exam preparation, enhances concept clarity, and improves problem-solving skills in Electrochemistry for CBSE and state board students.

Write the Nernst equation and calculate e.m.f of the following cell of 298 K.                  Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)                                                                                       Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V

Video solution:- 

Write the Nernst equation and calculate e.m.f of the following cell of 298 K.
Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)
Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V
Write the Nernst equation and calculate e.m.f of the following cell of 298 K. Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M) Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V

Welcome to Electrochemistry Class XII Chemistry Hub — your one-stop destination for mastering one of the most important chapters in Class 12 Chemistry across all education boards (CBSE, ICSE, ISC, and State Boards).

Here, you’ll find comprehensive notes, concept explanations, important questions, and previous year questions (PYQs) carefully organized to help you score high in board exams. Our resources cover every key topic — from galvanic and electrolytic cells to electrode potentials, Nernst equation, and electrochemical series — with clear, step-by-step solutions.

Whether you’re preparing for school exams, board exams, or competitive tests (JEE, NEET), this website provides exam-oriented study materialpractice questions, and PYQ analysis to strengthen your understanding and boost your confidence.

✨ Key Features:

  • Detailed Electrochemistry notes for Class XII Chemistry (All Boards)
  • Important and Most Expected Board Questions
  • Chapter-wise Previous Year Questions (PYQs)
  • Concept-based MCQs and Numerical Practice
  • Easy-to-understand explanations for quick revision

Start your preparation today and make Electrochemistry your strongest chapter!

Questions:-

1.  Write the balanced half-reactions occurring at the anode and cathode of the galvanic cell:
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)


2. Represent the cell in which the following reaction takes place

Mg(s)+2Ag+ (0.0001M)||Mg²+ (0.130M) + 2Ag(s)

Calculate its E (cell) if  E⁰ (cell) = 3.17V .


3.Calculate the emf of the cell in which the following reaction takes place:
Ni(s) + 2Ag+ (0.002 M) → Ni²+ (0.160 M) + 2Ag(s)
Given that E⁰cell = 1.05 V


4. A copper-silver cell is set up in which the concentration of copper ion is 0.10 M and the concentration of silver ion is not known. The cell potential when measured was found to be 0.422 V. Calculate the concentration of silver ions in the cell. The given cell reaction is:

Cu +2Ag+ → Cu²+ + 2Ag

(Given E°(Ag+/Ag) = +0.80V, E°(Cu²+/Cu) = +0.34 V), use antilog (1.29) = 19.5



6.Write the Nernst equation and emf of the following cells at 298 K:

Mg(s) |Mg²+ (0.001M)||Cu²+ (0.0001 M)|Cu(s)


7.Write the Nernst equation and emf of the following cells at 298 K:
(ii) Fe(s)|Fe²+ (0.001M)||H+(1M)| H2(g)(1bar)| Pt(s)


8.Write the Nernst equation and emf of the following cells at 298 K:

Sn(s)|Sn²+ (0.050M)||H+(0.020M)| H2(g)(1bar)| Pt(s)


9. Write the Nernst equation and emf of the following cells at 298 K:

Pt(s) | Br-(0.010M)|Br2(l)||H+(0.030M)| H2(g)(1bar)/ Pt(s).


10.Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

                   2Cr(s)+3Cd²+ (aq)    →  2Cr³+ (aq) + 3Cd
Calculate the ΔG°  and equilibrium constant of the reactions.


11. Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

Calculate the ΔG°  and equilibrium constant of the reactions.


12. What is the amount of electricity required to deposite one mole of aluminium from a solution   of AlCl3 ?


13.  A solution of Ni(NO3)2 is electrolysed between platinum electrode using a current of 5A for 30mint. What is the mass of Ni deposited at the cathode. The atomic mass of Ni=58.5g(amu). 


14.What is amount of electricity required to deposit one mole of calcium from molten  CaCl2 ?


15. What is amount of electricity required to deposit one mole of Zinc from ZnSO4?


16. Consider the reaction Cr2O7²- + 14H+  + 6e-  2Cr2+   +  7H2O.  What is the quantity of electricity            in coulombs needed to reduce 1 mole of Cr2O72-  ? 


17.Calculate the mass of silver deposited from silver nitrate solution by a current of 2 ampere                 flowing for 30 minutes. (Equivalent mass of silver is 108).


18. How many hours does it take to reduce 3 mol of Fe3+ to Fe2+ with 2.00 A current? (1 Faraday = 96,500 C mol-¹, R = 8.314JK-1 mol-1 ) 


19. What mass of zinc can be produced by electrolysis of zinc sulphate solution when current of 1.5 Ampere is passed for 15 minutes ?The atomic Mass of Zinc = 65.4 amu. 


20. If a current of 0.5 ampere flows through a metallic wire for 2 hours, then howmany electrons would flow through the wire?


21. The molar conductance of infinite dilution for sodium acetate ( CH3COONa) Hydrochloric acid (HCI) and sodium chloride (NaCl) are 92.5, 426.9 and 120.4 S cm²mol-¹ respectively at 298 K. calculate the molar conductance of Acetic Acid (CH3COOH) at infinite dilution.


22.Calculate the molar conductance of a solution of MgCl2 at infinite dilution, given that molar ionic Conductance of ∧⁰ (Mg²+) = 126.1Scm²mol-¹ and ∧⁰(Cl) = 56.3 Scm²mol-¹


23. Calculte molar conductance at infinite dilution for acetic acid, given ∧⁰HCI=425ohm−¹cm²mol−¹,∧⁰ NaCI=188ohm−¹cm²mol−¹,∧⁰  CH3COONa=96ohm−¹cm²mol−¹ 


24.  Given molar conductivities at infinite dilution ∧⁰m for Ba(OH)2 = 517.6 Ω−¹cm²mol−¹ ∧⁰m for BaCl2 = 240.6 Ω−¹cm²mol−¹, ∧⁰m for NH4Cl =  129.8Ω−¹cm²mol−¹ . Calculate ∧⁰m for NH4OH


25. The resistance of 0.25 M molar solution of an electrolyte was found to be 75 Ω.Calculate molar conductivity of the solution, if the electrodes in the cell are 1.8 cm apart and have an area of cross section 3.6 cm². 


26. The Resistance of 0.5 M solution of an electrolyte was found to be 30 Ω. Calculate the molar conductivity of the solution if the electrodes in the cell are 1.5 cm apart and having area of cross section 2.0 cm². 


27. The electrical Resistance of a column of 0.05 M NaOH solution of diameter 1cm and length 50 cm is 5.55 × 10³ Ω. Calculate its Molar conductivity.


28. The Resistance of a 0.5 N solution of an electrolyte in a conductivity cell was found to be 25 Ω. Calculate the equivalent conductivity if the electrodes in the cell are 1.6 cm apart and having an area cross section 3.2 cm². 


29. Write equation and calculate e.m.f of cell at 298 K.

Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)

Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V



Cu (s)/ Cu²+ (0.130M) || Ag+ / Ag(s) (1.0×10-⁴M)
E⁰Cu+/Cu = 0.34 V, E⁰Ag+/Ag = 0.80 V
Given, F = 96500 C, R = 8.314 JK-1 mol-1
 


Mg (s) |Mg²+ (0.001M)||Cu²+ (0.0001M)|Cu (s)
Given E⁰ Mg²+ / Mg =-2.37V, E⁰ Cu²+ /Cu =0.34 V
 


33. Write the Nernst equation and calculate e.m.f of the following cell of 298 K.

Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)
Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V
 


Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
 


Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe
Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V
November 08, 2025

Write equation and calculate e.m.f of cell at 298 K. Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s) Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V

Boost your Class 12 Chemistry exam preparation with this detailed electrochemistry solution. Learn how to write the cell reaction and calculate the EMF of the galvanic cell Mg(s) / Mg²⁺ (0.001 M) || Cu²⁺ (0.0001 M) / Cu(s) at 298 K. Using standard electrode potentials E°(Mg²⁺/Mg) = –2.37 V and E°(Cu²⁺/Cu) = 0.34 V, this post explains step-by-step how to determine the standard cell potential, Nernst equation application, and final EMF value. Perfect for CBSE Class 12 students and competitive exam aspirants.

Write equation and calculate e.m.f of cell at 298 K.
Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)

Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V
Video solution:- 



Write equation and calculate e.m.f of cell at 298 K.
Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)
Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V
Write equation and calculate e.m.f of cell at 298 K. Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s) Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V

Welcome to Electrochemistry Class XII Chemistry Hub — your one-stop destination for mastering one of the most important chapters in Class 12 Chemistry across all education boards (CBSE, ICSE, ISC, and State Boards).

Here, you’ll find comprehensive notes, concept explanations, important questions, and previous year questions (PYQs) carefully organized to help you score high in board exams. Our resources cover every key topic — from galvanic and electrolytic cells to electrode potentials, Nernst equation, and electrochemical series — with clear, step-by-step solutions.

Whether you’re preparing for school exams, board exams, or competitive tests (JEE, NEET), this website provides exam-oriented study materialpractice questions, and PYQ analysis to strengthen your understanding and boost your confidence.

✨ Key Features:

  • Detailed Electrochemistry notes for Class XII Chemistry (All Boards)
  • Important and Most Expected Board Questions
  • Chapter-wise Previous Year Questions (PYQs)
  • Concept-based MCQs and Numerical Practice
  • Easy-to-understand explanations for quick revision

Start your preparation today and make Electrochemistry your strongest chapter!

Questions:-

1.  Write the balanced half-reactions occurring at the anode and cathode of the galvanic cell:
Zn(s) + Cu²⁺(aq) → Zn²⁺(aq) + Cu(s)


2. Represent the cell in which the following reaction takes place

Mg(s)+2Ag+ (0.0001M)||Mg²+ (0.130M) + 2Ag(s)

Calculate its E (cell) if  E⁰ (cell) = 3.17V .


3.Calculate the emf of the cell in which the following reaction takes place:
Ni(s) + 2Ag+ (0.002 M) → Ni²+ (0.160 M) + 2Ag(s)
Given that E⁰cell = 1.05 V


4. A copper-silver cell is set up in which the concentration of copper ion is 0.10 M and the concentration of silver ion is not known. The cell potential when measured was found to be 0.422 V. Calculate the concentration of silver ions in the cell. The given cell reaction is:

Cu +2Ag+ → Cu²+ + 2Ag

(Given E°(Ag+/Ag) = +0.80V, E°(Cu²+/Cu) = +0.34 V), use antilog (1.29) = 19.5



6.Write the Nernst equation and emf of the following cells at 298 K:

Mg(s) |Mg²+ (0.001M)||Cu²+ (0.0001 M)|Cu(s)


7.Write the Nernst equation and emf of the following cells at 298 K:
(ii) Fe(s)|Fe²+ (0.001M)||H+(1M)| H2(g)(1bar)| Pt(s)


8.Write the Nernst equation and emf of the following cells at 298 K:

Sn(s)|Sn²+ (0.050M)||H+(0.020M)| H2(g)(1bar)| Pt(s)


9. Write the Nernst equation and emf of the following cells at 298 K:

Pt(s) | Br-(0.010M)|Br2(l)||H+(0.030M)| H2(g)(1bar)/ Pt(s).


10.Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

                   2Cr(s)+3Cd²+ (aq)    →  2Cr³+ (aq) + 3Cd
Calculate the ΔG°  and equilibrium constant of the reactions.


11. Calculate the standard cell potentials of galvanic cell in which the following reactions take place:

Calculate the ΔG°  and equilibrium constant of the reactions.


12. What is the amount of electricity required to deposite one mole of aluminium from a solution   of AlCl3 ?


13.  A solution of Ni(NO3)2 is electrolysed between platinum electrode using a current of 5A for 30mint. What is the mass of Ni deposited at the cathode. The atomic mass of Ni=58.5g(amu). 


14.What is amount of electricity required to deposit one mole of calcium from molten  CaCl2 ?


15. What is amount of electricity required to deposit one mole of Zinc from ZnSO4?


16. Consider the reaction Cr2O7²- + 14H+  + 6e-  2Cr2+   +  7H2O.  What is the quantity of electricity            in coulombs needed to reduce 1 mole of Cr2O72-  ? 


17.Calculate the mass of silver deposited from silver nitrate solution by a current of 2 ampere                 flowing for 30 minutes. (Equivalent mass of silver is 108).


18. How many hours does it take to reduce 3 mol of Fe3+ to Fe2+ with 2.00 A current? (1 Faraday = 96,500 C mol-¹, R = 8.314JK-1 mol-1 ) 


19. What mass of zinc can be produced by electrolysis of zinc sulphate solution when current of 1.5 Ampere is passed for 15 minutes ?The atomic Mass of Zinc = 65.4 amu. 


20. If a current of 0.5 ampere flows through a metallic wire for 2 hours, then howmany electrons would flow through the wire?


21. The molar conductance of infinite dilution for sodium acetate ( CH3COONa) Hydrochloric acid (HCI) and sodium chloride (NaCl) are 92.5, 426.9 and 120.4 S cm²mol-¹ respectively at 298 K. calculate the molar conductance of Acetic Acid (CH3COOH) at infinite dilution.


22.Calculate the molar conductance of a solution of MgCl2 at infinite dilution, given that molar ionic Conductance of ∧⁰ (Mg²+) = 126.1Scm²mol-¹ and ∧⁰(Cl) = 56.3 Scm²mol-¹


23. Calculte molar conductance at infinite dilution for acetic acid, given ∧⁰HCI=425ohm−¹cm²mol−¹,∧⁰ NaCI=188ohm−¹cm²mol−¹,∧⁰  CH3COONa=96ohm−¹cm²mol−¹ 


24.  Given molar conductivities at infinite dilution ∧⁰m for Ba(OH)2 = 517.6 Ω−¹cm²mol−¹ ∧⁰m for BaCl2 = 240.6 Ω−¹cm²mol−¹, ∧⁰m for NH4Cl =  129.8Ω−¹cm²mol−¹ . Calculate ∧⁰m for NH4OH


25. The resistance of 0.25 M molar solution of an electrolyte was found to be 75 Ω.Calculate molar conductivity of the solution, if the electrodes in the cell are 1.8 cm apart and have an area of cross section 3.6 cm². 


26. The Resistance of 0.5 M solution of an electrolyte was found to be 30 Ω. Calculate the molar conductivity of the solution if the electrodes in the cell are 1.5 cm apart and having area of cross section 2.0 cm². 


27. The electrical Resistance of a column of 0.05 M NaOH solution of diameter 1cm and length 50 cm is 5.55 × 10³ Ω. Calculate its Molar conductivity.


28. The Resistance of a 0.5 N solution of an electrolyte in a conductivity cell was found to be 25 Ω. Calculate the equivalent conductivity if the electrodes in the cell are 1.6 cm apart and having an area cross section 3.2 cm². 


29. Write equation and calculate e.m.f of cell at 298 K.

Mg(s) / Mg²+ (0.001M)|| Cu²+ (0.0001M)/Cu(s)

Given E⁰Mg²+/Mg(s) = - 2.37 V, E⁰cu²+/Cu(s) = 0.34 V



Cu (s)/ Cu²+ (0.130M) || Ag+ / Ag(s) (1.0×10-⁴M)
E⁰Cu+/Cu = 0.34 V, E⁰Ag+/Ag = 0.80 V
Given, F = 96500 C, R = 8.314 JK-1 mol-1
 


Mg (s) |Mg²+ (0.001M)||Cu²+ (0.0001M)|Cu (s)
Given E⁰ Mg²+ / Mg =-2.37V, E⁰ Cu²+ /Cu =0.34 V
 


33. Write the Nernst equation and calculate e.m.f of the following cell of 298 K.

Ni|Ni²+ (0.01M)||Cu²+ | Cu(0.01M)
Given E⁰(Cu²+/Cu) = 0.34V, E⁰ (Ni²+ /Ni) =-0.22V
 


Mg(s)|Mg²+ (0.130M)| |Ag+(1.0×10-⁴M)|Ag(s)
Given, E⁰ Ag+ /Ag =0.80 V, E (Mg²+ / Mg ) =-2.36 V
 


Cr | Cr³+ (0.1M) || Fe²+ (0.01M) | Fe
Given,  E⁰(Cr³+/Cr) = -0.75V,   E⁰(Fe²+ /Fe) = -0.45V