Aşağıdaki tepkimelerden hangisinin entalpi değişimi $(\Delta H)$, standart molar oluşum entalpisine $(\Delta H_f^\circ)$ eşit değildir?
A) $\text{H}_2 \text{(g)} + \frac{1}{2}\text{O}_2 \text{(g)} \to \text{H}_2\text{O (s)}$
B) $\text{C (grafit)} + \text{O}_2 \text{(g)} \to \text{CO}_2 \text{(g)}$
C) $\text{N}_2 \text{(g)} + 3\text{H}_2 \text{(g)} \to 2\text{NH}_3 \text{(g)}$
D) $\text{Na (k)} + \frac{1}{2}\text{Cl}_2 \text{(g)} \to \text{NaCl (k)}$
E) $\text{CH}_4 \text{(g)} + 2\text{O}_2 \text{(g)} \to \text{CO}_2 \text{(g)} + 2\text{H}_2\text{O (s)}$
