Which equation corresponds to the standard enthalpy of formation of sodium oxide?
- A$\text{Na(s)} + \tfrac{1}{4}\text{O}_2\text{(g)} \rightarrow \tfrac{1}{2}\text{Na}_2\text{O(s)}$
- B$\text{Na(s)} + \text{O}_2\text{(g)} \rightarrow \text{Na}_2\text{O(s)}$
- C$2\text{Na(s)} + \tfrac{1}{2}\text{O}_2\text{(g)} \rightarrow \text{Na}_2\text{O(s)}$
- D$4\text{Na(s)} + \text{O}_2\text{(g)} \rightarrow 2\text{Na}_2\text{O(s)}$