How many steps are involved in the Born-Harber cycle for sodium chloride?

Options

A. Four
B. Five
C. Six
D. Seven

Explanation

To determine how many steps are involved in the Born-Haber cycle for sodium chloride (NaCl), we can break down the process into distinct stages. The Born-Haber cycle is a thermodynamic cycle that relates the lattice energy of an ionic compound to its formation from its constituent elements. Here are the steps involved:

### Step-by-step Solution:

1. **Sublimation of Sodium (Na)**:
- The first step involves converting solid sodium (Na) into gaseous sodium (Na(g)). This process requires energy and is known as sublimation.
- **Energy Change**: This is represented by the heat of sublimation.

2. **Dissociation of Chlorine (Cl2)**:
- The second step involves the dissociation of chlorine gas (Cl2) into two chlorine atoms (Cl). This process also requires energy.
- **Energy Change**: This is represented by the bond dissociation energy of Cl2.

3. **Ionization of Sodium (Na)**:
- The third step is the ionization of gaseous sodium (Na(g)) to form sodium ions (Na+). This process requires energy to remove an electron from Na.
- **Energy Change**: This is represented by the ionization energy of sodium.

4. **Electron Affinity of Chlorine (Cl)**:
- The fourth step involves the gain of an electron by a chlorine atom (Cl) to form a chloride ion (Cl-). This process releases energy.
- **Energy Change**: This is represented by the electron affinity of chlorine.

5. **Formation of Sodium Chloride (NaCl)**:
- The final step is the formation of solid sodium chloride (NaCl) from gaseous sodium ions (Na+) and chloride ions (Cl-). This process releases a significant amount of energy.
- **Energy Change**: This is represented by the lattice energy of NaCl.

### Conclusion:
In total, there are **five steps** involved in the Born-Haber cycle for sodium chloride.