MCQ
Which of the reaction defines $\Delta H_f^o$ ?
- ✓$\frac{1}{2}{H_2}(g) + \frac{1}{2}{F_2}(g) \to HF(g)$
- B$CO(g) + \frac{1}{2}{O_2}(g) \to C{O_2}(g)$
- C${C_{{\rm{diamond}}}} + {O_2}(g) \to C{O_2}(g)$
- D${N_2}(g) + 3{H_2}(g) \to 2N{H_3}(g)$
✓
Answer
Correct option: A.
$\frac{1}{2}{H_2}(g) + \frac{1}{2}{F_2}(g) \to HF(g)$
a
The standard enthalpy of formation $\left(\Delta H _{ f }^0\right)$ is the enthalpy change during formation of $1\, mole$ of substance when its constituent elements are in their standard states.
The standard enthalpy of formation $\left(\Delta H _{ f }^0\right)$ is the enthalpy change during formation of $1\, mole$ of substance when its constituent elements are in their standard states.
Only $(A)$ follows the definition of $\Delta H _{ f }^0$. Therefore, $(A)$ is correct answer.
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