Which of the following element will have highest ionization energy?

Options

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

Explanation

To determine which element has the highest ionization energy among the given options, we can follow these steps:

### Step-by-Step Solution:

1. **Understand Ionization Energy**:
Ionization energy is defined as the minimum energy required to remove an electron from an atom in its gaseous state. Generally, elements with a higher effective nuclear charge and those that are closer to having a full outer shell will have higher ionization energies.

2. **Identify the Elements**:
Let’s assume the options provided are:
- Option 1: Element A (e.g., Lithium, Li)
- Option 2: Element B (e.g., Carbon, C)
- Option 3: Element C (e.g., Oxygen, O)
- Option 4: Element D (e.g., Neon, Ne)

3. **Consider the Electron Configuration**:
- Element A (Li): 1s² 2s¹
- Element B (C): 1s² 2s² 2p²
- Element C (O): 1s² 2s² 2p⁴
- Element D (Ne): 1s² 2s² 2p⁶

4. **Analyze the Penetration Power of Subshells**:
The penetration power of subshells is ranked as follows:
- s > p > d > f
This means that electrons in the s subshell are held more tightly by the nucleus compared to those in the p subshell.

5. **Evaluate the Last Electron Added**:
- For Element A (Li), the last electron is in the 2s subshell.
- For Element B (C), the last electron is in the 2p subshell.
- For Element C (O), the last electron is also in the 2p subshell.
- For Element D (Ne), the last electron is in the 2p subshell.

6. **Determine the Ionization Energy Trend**:
- Generally, ionization energy increases across a period (left to right) and decreases down a group (top to bottom).
- Since Ne has a full outer shell (2s² 2p⁶), it will have the highest ionization energy among the given options because it is more stable and requires more energy to remove an electron.

7. **Conclusion**:
Based on the analysis, **Element D (Neon)** will have the highest ionization energy.

### Final Answer:
**Element D (Neon)** has the highest ionization energy.