Calculate the heat of formation of NaCl from the following data:
Heat of sublimation of sodium = `108.5 kJ mol^(-1)`
Dissociation energy of chlorine = `243.0 kJ mol^(-1) `
lonisation energy of sodium = 495.8 kJ `mol^(-1)`
Electron gain enthalpy of chlorine `= -348.8 kJ mol^(-1)`
Lattice energy of sodium chloride `= -758.7 kJ mol^(-1)`.

Explanation

To calculate the heat of formation (ΔHf) of NaCl using the provided data, we can apply the Born-Haber cycle. The Born-Haber cycle allows us to break down the formation of an ionic compound into several steps, each associated with a specific energy change.

### Step-by-Step Solution:

1. **Write the formation reaction**:
The formation of NaCl from its elements can be represented as:
\[
\text{Na (s)} + \frac{1}{2} \text{Cl}_2 (g) \rightarrow \text{NaCl (s)}
...