UPSC Combined Geo-Scientist, Mains · 2020 · Mains Paper II
Q7(b). Enthalpy of the hydrogen–silver chloride cell
Question
The cell Pt|H₂(g)|HCl(aq)|AgCl(s)|Ag(s) has emf 0.265 V at 25° C and 0.260 V at 35° C. Calculate its reaction enthalpy at 25° C.
Answer in brief
ΔᵣH=-79.9 kJ mol⁻¹ for H₂ + 2AgCl → 2H⁺ + 2Cl⁻ + 2Ag.
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CoversEnthalpy of the hydrogen–silver chloride cellElectrochemistry
All parts of Question 7
- 7(a) Thermodynamic parameters from emf5 marks
- 7(b) Enthalpy of the hydrogen–silver chloride cell5 marks