The electronic configuration of the atom having maximum difference in first and second ionzation enthalpies is

Options

A. `1s^(2) 2s^(2) 2p^(6) 3s^(2)`
B. `1s^(2)2s^(2) 2p^(6)3s^(2) 3p^(1)`
C. `1s^(2) 2s^(2) 2p^(6)3s^(2)3p^(2)`
D. `1s^(2)2s^(2) 2p^(6)3s^(1)`

Answer

To determine the electronic configuration of the atom having the maximum difference in first and second ionization enthalpies, we need to analyze the given options and understand the concept of ionization enthalpy.

### Step-by-Step Solution:

1. **Understand Ionization Enthalpy**:
- The first ionization enthalpy (IE1) is the energy required to remove the first electron from an atom.
- The second ionization enthalpy (IE2) is the energy required to remove the second electron after the first has been removed.
- The difference between IE1 and IE2 can be significant when the removal of the second electron leads to a more stable electron configuration.

2. **Analyze the Given Options**:
- **Option A**: 1s² 2s² 2p⁶ 3s¹
- **Option B**: 1s² 2s² 2p⁶ 3s²
- **Option C**: 1s² 2s² 2p⁶ 3s² 3p¹
- **Option D**: 1s² 2s² 2p⁶ (Neon configuration)

3. **Identify the Stability of Configurations**:
- **Option A** (3s¹): Removing the first electron leads to a stable noble gas configuration (Neon). The second ionization would require a lot more energy as it disrupts a stable configuration.
- **Option B** (3s²): The second ionization would not be as large because both electrons are in the same subshell.
- **Option C** (3s² 3p¹): Similar reasoning as option B; the removal of the second electron from a p-orbital does not lead to a significant change in stability.
- **Option D** (Neon): This is a noble gas configuration. Removing one electron would lead to a more stable configuration, but the difference in ionization energies is not maximized here.

4. **Conclusion**:
- The maximum difference in ionization enthalpies occurs in **Option A** (1s² 2s² 2p⁶ 3s¹) because removing the first electron leads to a noble gas configuration, while removing the second electron would require significantly more energy due to the instability of the resulting configuration.

5. **Final Answer**: The electronic configuration of the atom having maximum difference in first and second ionization enthalpies is **1s² 2s² 2p⁶ 3s¹**.