The answer is D glad to help :)<span />
Answer:
A sodium atom has one electron in the outer shell. A chlorine atom seven electrons in the outer shell. A sodium atom loses an electron to a chlorine atom. The sodium atom becomes a positive sodium ion.
The molecular weight of H2O is 18g/mol.
Therefore, 27.9 g H2O / (1mol/18g) = 0.155 mol H2O
Calculating only for the latent heat, the heat required to be released for this amount of H2O to condense is:
40.7 kJ/mol (0.155 mol) = 6.3 kJ or -6.3 kJ since it is to be released