Which of the following processes requires maximum energy

Options

A. `Mg(g)rarrMg^(+)(g)+e^(-)`
B. `Mg^(+)(g)rarr Mg^(+2)(g)+e^(-)`
C. `Na(g)rarrNa^(+)(g)+e^(-)`
D. `Na^(+)(g)rarr Na^(2+)(g)+e^(-)`

Answer

To determine which of the following processes requires the maximum energy, we need to analyze the ionization energies involved in each process. Ionization energy is the energy required to remove an electron from an atom or ion.

### Step-by-Step Solution:

1. **Identify the Electronic Configurations**:
- **Magnesium (Mg)**: The electronic configuration is \( \text{Ne} \, 3s^2 \).
- **Sodium (Na)**: The electronic configuration is \( \text{Ne} \, 3s^1 \).

2. **Determine the Ionization Processes**:
- For **Mg**:
- First ionization: \( \text{Mg} \rightarrow \text{Mg}^+ + e^- \)
- Second ionization: \( \text{Mg}^+ \rightarrow \text{Mg}^{2+} + e^- \)
- For **Na**:
- First ionization: \( \text{Na} \rightarrow \text{Na}^+ + e^- \)
- Second ionization: \( \text{Na}^+ \rightarrow \text{Na}^{2+} + e^- \)

3. **Analyze Ionization Energies**:
- The first ionization of both Mg and Na will require energy, but the second ionization of Mg (from \( \text{Mg}^+ \) to \( \text{Mg}^{2+} \)) will require more energy than the second ionization of Na (from \( \text{Na}^+ \) to \( \text{Na}^{2+} \)).
- This is because the \( \text{Mg}^+ \) ion has a stable noble gas configuration (Neon) after losing one electron, making it harder to remove another electron.

4. **Consider the Stability of the Ions**:
- **Mg** after losing two electrons achieves a stable noble gas configuration (\( \text{Ne} \)).
- **Na** after losing one electron also achieves a stable noble gas configuration (\( \text{Ne} \)), but the second ionization (removing an electron from a noble gas configuration) is highly unfavorable.

5. **Conclusion**:
- The process that requires the maximum energy is the second ionization of sodium (\( \text{Na}^+ \rightarrow \text{Na}^{2+} \)), as it involves removing an electron from a stable noble gas configuration.

### Final Answer:
The process that requires maximum energy is the second ionization of sodium, which is represented as \( \text{Na}^+ \rightarrow \text{Na}^{2+} \).