Answer:
B: Na(s) + Cl2(g) + 3O2(g) = 2NaClO3(s)
Explanation:
We are looking for enthalpy of formation, so we want to see reactance in their natural standard form.
Thus, we want to see the reactance of Na, Cl2 and O2.
The only option that has the correct form of Na, Cl2 and O2 is B.
Na(s) + Cl2(g) + 3O2(g) = 2NaClO3(s)
