The correct pair regarding property given in bracket is

Options

A. `F_(2) gt Cl_(2)` (Oxidising character)
B. `F gt Cl` (Electron affinity)
C. `F lt Cl` (Electronegativity)
D. `O gt N` (Ionisation energy)

Answer

To solve the question regarding the correct pair of properties, we will analyze each option one by one:

### Step 1: Analyze Option 1 - F2 has greater oxidizing character than Cl2
- **Definition**: Oxidizing character refers to the ability of a substance to oxidize another substance, which is related to its reduction potential.
- **Comparison**: Fluorine (F2) has a more positive reduction potential compared to chlorine (Cl2). This means that F2 can easily gain electrons and thus oxidizes other substances more effectively.
- **Conclusion**: This statement is **correct**.

### Step 2: Analyze Option 2 - Fluorine has more electron affinity than Chlorine
- **Definition**: Electron affinity is the energy change when an electron is added to a neutral atom.
- **Comparison**: Although fluorine has a high electron affinity due to its small size and high nuclear charge, it experiences significant inter-electronic repulsion due to its small size and the presence of 7 electrons in the outer shell (2p5). This makes it less favorable to gain an additional electron compared to chlorine.
- **Conclusion**: This statement is **incorrect**.

### Step 3: Analyze Option 3 - Chlorine has more electronegativity than Fluorine
- **Definition**: Electronegativity is the tendency of an atom to attract electrons in a bond.
- **Comparison**: Fluorine is the most electronegative element in the periodic table, while chlorine is less electronegative. Thus, fluorine has a higher electronegativity than chlorine.
- **Conclusion**: This statement is **incorrect**.

### Step 4: Analyze Option 4 - Oxygen has greater ionization energy than Nitrogen
- **Definition**: Ionization energy is the energy required to remove an electron from an atom.
- **Comparison**: Generally, ionization energy increases across a period. However, nitrogen has a half-filled p orbital (2p3 configuration), which is more stable than oxygen's (2p4 configuration). Therefore, nitrogen has a higher ionization energy than oxygen.
- **Conclusion**: This statement is **incorrect**.

### Final Conclusion
After analyzing all options, we find that:
- Option 1 is the only correct statement: **F2 has greater oxidizing character than Cl2**.

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