Thermodynamics And Thermochemistry Result Question 11
- Which of the following reactions defines $\Delta H^{\circ} _f$ ?
(2003, 1M)
(a) $\mathrm{C} _{\text {(diamond) }}+\mathrm{O} _2(g) \longrightarrow \mathrm{CO} _2(g)$
(b) $\frac{1}{2} \mathrm{H} _2(g)+\frac{1}{2} \mathrm{~F} _2(g) \longrightarrow \mathrm{HF}(g)$
(c) $\mathrm{N} _2(g)+3 \mathrm{H} _2(g) \longrightarrow 2 \mathrm{NH} _3(g)$
(d) $\mathrm{CO}(g)+\frac{1}{2} \mathrm{O} _2(g) \longrightarrow \mathrm{CO} _2(g)$
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Answer:
Correct Answer: 11. ( b )
Solution:
- $\frac{1}{2} \mathrm{H} _2(g)+\frac{1}{2} \mathrm{~F} _2(g) \longrightarrow \mathrm{HF}(g)$
Here $ \Delta H^{\circ}=\text { Standard molar enthalpy of formation of } \mathrm{HF}(\mathrm{g}) \text {. }$
BETA
