Choose the incorrect statements from the following:

Options

A. Ionization energy of atom may be negative.
B. Ionization energy of an ion may be negative.
C. Ionization energy is inverscly proportional to radius.
D. Electron present in p orbital is in need of less energy for its removal as compared to electron present in d orbital having the same principal quantum number.

Answer

To solve the question of identifying the incorrect statements regarding ionization energy, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Understanding Ionization Energy**:
- Ionization energy is defined as the energy required to remove the outermost electron from an atom or ion.
- It is always a positive value because energy must be supplied to overcome the attraction between the nucleus and the electron.

2. **Analyzing Statement 1**:
- **Statement**: "Ionization energy of atom may be negative."
- **Analysis**: This statement is incorrect because ionization energy cannot be negative. It is always a positive value.
- **Conclusion**: This statement is incorrect.

3. **Analyzing Statement 2**:
- **Statement**: "Ionization energy of an ion may be negative."
- **Analysis**: Similar to the first statement, ionization energy for any atom or ion cannot be negative. It requires energy to remove an electron.
- **Conclusion**: This statement is also incorrect.

4. **Analyzing Statement 3**:
- **Statement**: "Ionization energy is inversely proportional to radius."
- **Analysis**: This statement is correct. As the radius of an atom increases, the outermost electrons are farther from the nucleus, resulting in a weaker attraction and lower ionization energy.
- **Conclusion**: This statement is correct.

5. **Analyzing Statement 4**:
- **Statement**: "Electron present in P orbital is in need of less energy for its removal as compared to electron present in D orbital having the same principal quantum number."
- **Analysis**: This statement is incorrect. Electrons in the D orbital are generally at a higher energy level and are farther from the nucleus compared to P orbital electrons in the same principal quantum number. Therefore, it requires more energy to remove an electron from a D orbital than from a P orbital.
- **Conclusion**: This statement is incorrect.

### Final Conclusion:
The incorrect statements are:
- Statement 1: "Ionization energy of atom may be negative."
- Statement 2: "Ionization energy of an ion may be negative."
- Statement 4: "Electron present in P orbital is in need of less energy for its removal as compared to electron present in D orbital having the same principal quantum number."