Question

The lattice energy for sodium chloride, NaCl, is 790. kJ/mol. Use this information and the information below to calculate the enthalpy of reaction for the combination of sodium metal (Na(s)) with chlorine gas (Cl2(g)) to form NaCl.

reaction (1): Na(s) → Na(g) ΔH1 = 108 kJ/mol

reaction (2): Na(g) → Na+(g) + e− ΔH2 = 388 kJ/mo

reaction (3): 1/2 Cl2(g) → Cl(g) ΔH3 = 121 kJ/mol

reaction (4): Cl(g) + e− → Cl −(g) ΔH4 = −348 kJ/mol