Q47.The standard electrode potential Eo and its temperature coefficient ( dTdE ) for a cell are 2 V and −5×10−4 V K−1 at 300 K, respectively. The reaction is Zn (s) + Cu2+ (aq) →Zn2+ (aq) + Cu (s). The standard reaction enthalpy (ΔrH−) at 300 K in mol−1 is [Use R = 8 J K−1 mol−1 and F =96,500 C mol−1] (1) −412.8 (2) 206.4 (3) −384.0 (4) 192.0
What This Question Tests
This question tests the ability to relate standard electrode potential, its temperature coefficient, and Gibbs free energy to calculate standard reaction enthalpy using thermodynamic relations for electrochemical cells.
Concepts Tested
Formulas Used
ΔG° = -nFE°
ΔG° = ΔH° - TΔS°
ΔS° = nF(dE°/dT)
📚 NCERT Sections This Tests
2.4 — Calculate The Standard Cell Potentials Of Galvanic Cell In Which The Following
Chemistry Class 11 · Chapter 2
2.4 Calculate the standard cell potentials of galvanic cell in which the following reactions take place: (i) 2Cr(s) + 3Cd2+(aq) ® 2Cr3+(aq) + 3Cd (ii) Fe2+(aq) + Ag+(aq) ® Fe3+(aq) + Ag(s) Calculate the DrGo and equilibrium constant of the reactions. 2.5 Write the Nernst equation and emf of the following cells at 298 K: (i) Mg(s)|Mg2+(0.001M)||Cu2+(0.0001 M)|Cu(s) (ii) Fe(s)|Fe2+(0.001M)||H+(1M)|H2(g)(1bar)| Pt(s) (iii) Sn(s)|Sn2+(0.050 M)||H+(0.020 M)|H2(g) (1 bar)|Pt(s) (iv) Pt(s)|Br–(0.010 M)|Br2(l )||H+(0.030 M)| H2(g) (1 bar)|Pt(s).
2.6 — In The Button Cells Widely Used In Watches And Other Devices The Following
Chemistry Class 11 · Chapter 2
2.6 In the button cells widely used in watches and other devices the following reaction takes place: Zn(s) + Ag2O(s) + H2O(l) ® Zn2+(aq) + 2Ag(s) + 2OH–(aq) Determine DrGo and Eo for the reaction.
2.3 — Depict The Galvanic Cell In Which The Reaction
Chemistry Class 11 · Chapter 2
2.3 Depict the galvanic cell in which the reaction Zn(s)+2Ag+(aq) ®Zn2+(aq)+2Ag(s) takes place. Further show: (i) Which of the electrode is negatively charged? (ii) The carriers of the current in the cell. (iii) Individual reaction at each electrode.
📋 Question Details
- Chapter
- Electrochemistry
- Topic
- Thermodynamics of electrochemical cells
- Year
- 2019
- Shift
- 12 Jan Shift 1
- Q Number
- Q47
- Type
- MCQ
- NCERT Ref
- Class 12 Chemistry Ch 3: Electrochemistry
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