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For which one of the following equations is Δ H_ react ° equal to Δ H_f° for the product?

NEET UG 2003 — Chemistry Physical Chemistry

2003mcqhard

For which one of the following equations is ΔHreact ∘\Delta \mathrm{H}_{\text {react }}^{\circ}ΔHreact ∘​ equal to ΔHf∘\Delta \mathrm{H}_f^{\circ}ΔHf∘​ for the product?

Official previous-year question

Held on 30 Apr 2003 · Verified 9 Jul 2026.

Options

  1. A

    N2(g)+O3(g)→N2O3(g)\mathrm{N}_{2(g)}+\mathrm{O}_{3(g)} \rightarrow \mathrm{N}_2 \mathrm{O}_3(g)N2(g)​+O3(g)​→N2​O3​(g)

  2. B

    CH4(g)+2Cl2( g)→CH2Cl2(l)+\mathrm{CH}_{4(g)}+2 \mathrm{Cl}_{2(\mathrm{~g})} \rightarrow \mathrm{CH}_2 \mathrm{Cl}_{2(l)}+CH4(g)​+2Cl2( g)​→CH2​Cl2(l)​+ 2HCl(g)2 \mathrm{HCl}_{(g)}2HCl(g)​

  3. C

    Xe(g)+2 F2(g)→XeF4(g)\mathrm{Xe}_{(g)}+2 \mathrm{~F}_{2(g)} \rightarrow \mathrm{XeF}_{4(g)}Xe(g)​+2 F2(g)​→XeF4(g)​

  4. D

    2CO(g)+O2(g)→2CO2(g)2 \mathrm{CO}_{(g)}+\mathrm{O}_{2(g)} \rightarrow 2 \mathrm{CO}_{2(g)}2CO(g)​+O2(g)​→2CO2(g)​

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