Electron affinity of carbon is greater than nitrogen because:

Options

A. carbon shows catenation
B. entering electron occupies 2p orbital of carbon
C. carbon accept one electron and assumes `[He]2s^2 ""2p_x^1""2p_y^1""2p_z^1` structure
D. All the above are correct

Answer

To answer the question of why the electron affinity of carbon is greater than that of nitrogen, we can break down the explanation into several steps:

### Step-by-Step Solution:

1. **Understanding Electron Affinity**:
- Electron affinity is defined as the amount of energy released when an electron is added to a neutral atom in the gas phase. A higher electron affinity indicates that an atom more readily accepts an electron.

2. **Electron Configuration**:
- Carbon (C) has an atomic number of 6, and its electron configuration is \(1s^2 2s^2 2p^2\).
- Nitrogen (N) has an atomic number of 7, and its electron configuration is \(1s^2 2s^2 2p^3\).

3. **Stability of Electron Configurations**:
- The electron configuration of nitrogen is \(2p^3\), which is a half-filled configuration. Half-filled and fully filled subshells are generally more stable due to symmetry and exchange energy.
- Carbon, with its \(2p^2\) configuration, is not half-filled. When it gains an electron, it achieves a half-filled configuration of \(2p^3\).

4. **Energy Considerations**:
- For carbon, adding an electron to achieve the \(2p^3\) configuration releases energy, making the process favorable.
- For nitrogen, adding an electron would disturb the stable half-filled \(2p^3\) configuration, which requires energy input rather than releasing energy.

5. **Conclusion**:
- Therefore, carbon has a greater electron affinity than nitrogen because it can achieve a more stable electron configuration upon gaining an electron, while nitrogen's half-filled configuration makes it less favorable to accept an additional electron.

### Final Answer:
The electron affinity of carbon is greater than that of nitrogen because when carbon accepts an electron, it achieves a stable half-filled configuration (\(2p^3\)), while nitrogen, already in a half-filled state, would have to disturb this stability to gain an electron, making the process less favorable.

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