which of the following configurations represents atoms of the elements having the highest second ionisation energy?

Options

A. `1s^(2)2s^(2)2p^(4)`
B. `1s^(2)2s^(2)2p^(6)`
C. `1s^(2)2s^(2)2p^(6)3s^(1)`
D. `1s^(2)2s^(2)2p^(6)3s^(2)`

Answer

To determine which electron configuration corresponds to the element with the highest second ionization energy, we need to understand the concept of ionization energy and how electron configurations affect it. Here’s a step-by-step solution:

### Step 1: Understand Ionization Energy
Ionization energy is the energy required to remove an electron from an atom in the gaseous state. The second ionization energy specifically refers to the energy needed to remove a second electron after the first has already been removed.

**Hint:** Remember that the stability of an electron configuration influences the amount of energy required to remove electrons.

### Step 2: Analyze Electron Configurations
We need to analyze the given electron configurations. Common configurations to consider might include:
- 2p3 (which corresponds to nitrogen)
- 2p6 (which corresponds to neon)
- 3s1 (which corresponds to sodium)
- 2p5 (which corresponds to fluorine)

**Hint:** Look for configurations that are either fully filled or half-filled, as these tend to have higher ionization energies.

### Step 3: Identify Stable Configurations
- **2p3**: This is a half-filled configuration. Half-filled subshells are relatively stable but not as stable as fully filled subshells.
- **2p6**: This is a fully filled configuration. Fully filled subshells are very stable and require more energy to remove an electron.
- **3s1**: This configuration has one electron in the outermost shell, which is less stable and requires less energy to remove.
- **2p5**: This configuration is one electron short of being fully filled and is relatively stable but not as stable as 2p6.

**Hint:** Fully filled configurations (like 2p6) will generally have the highest second ionization energy due to their stability.

### Step 4: Compare Ionization Energies
When comparing the second ionization energies:
- Removing an electron from a fully filled configuration (2p6) requires more energy because the atom is stable and more energy is needed to disturb that stability.
- The half-filled configuration (2p3) will require less energy than the fully filled configuration but more than an unstable configuration like 3s1.

**Hint:** The more stable the electron configuration, the higher the ionization energy required to remove an electron.

### Step 5: Conclusion
Based on the analysis, the electron configuration that represents the atom with the highest second ionization energy is **2p6** (fully filled configuration).

**Final Answer:** The configuration that represents the atom with the highest second ionization energy is **2p6**.