UPSC Civil Services (Mains), Chemistry optional · 2024 · Paper I
Q3(c)(iii). Pressure of O₂ over NiO at 25 °C
Question
Calculate the pressure of O₂ (in atm) over a sample of NiO at 25 °C if ΔG° = 212 kJ mol⁻¹ for the reaction NiO(s) ⇌ Ni(s) + ½O₂(g).
Answer in brief
p(O₂) = 4.8 × 10⁻⁷⁵ atm.
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Coversstandard Gibbs energyequilibrium constantdecomposition pressureNiOheterogeneous equilibrium
All parts of Question 3
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- 3(c)(i) Change in Helmholtz energy on reversible isothermal compression10 marks
- 3(c)(ii) Why a tyre gets hot when it is pumped5 marks
- 3(c)(iii) Pressure of O₂ over NiO at 25 °C5 marks
- 3(c)(iv) Final temperature after Joule–Thomson expansion5 marks