Assertion: `F` is more electronegative than `Cl`.
Reason: `F` has high electron affinity than `Cl`.

Options

A. If both assertion and reason are true and reason is the correct explanation of assertion
B. If both assertion and reason are true but reason is not the correct explanation of assertion
C. If assertion is true but reasonb is false
D. If both assertion and reason are false.

Explanation

To analyze the given assertion and reason, we will break down the concepts of electronegativity and electron affinity step by step.

### Step-by-Step Solution:

1. **Understanding the Assertion:**
- The assertion states that fluorine (F) is more electronegative than chlorine (Cl).
- **Electronegativity** is defined as the ability of an atom to attract shared electrons in a chemical bond.

2. **Comparing Electronegativity of F and Cl:**
- Fluorine is located above chlorine in the periodic table.
- As we move down a group in the periodic table, the atomic number increases, leading to an increase in the number of electron shells.
- Fluorine has fewer electron shells compared to chlorine, which means its valence electrons are closer to the nucleus. This results in a stronger attraction for shared electrons.
- Therefore, the assertion that fluorine is more electronegative than chlorine is **correct**.

3. **Understanding the Reason:**
- The reason states that fluorine has a higher electron affinity than chlorine.
- **Electron affinity** is the amount of energy released when an electron is added to a neutral atom in the gas phase.
- While fluorine does have a high electron affinity, it is not higher than that of chlorine. Chlorine has a larger atomic radius and can accommodate an additional electron more easily due to the presence of vacant d-orbitals.
- Therefore, the statement that fluorine has a higher electron affinity than chlorine is **incorrect**.

4. **Conclusion:**
- The assertion is true: Fluorine is more electronegative than chlorine.
- The reason is false: Fluorine does not have a higher electron affinity than chlorine.
- Thus, we conclude that the assertion is correct, but the reason is incorrect.

### Final Answer:
- The correct option is: **Assertion is true, Reason is false.**

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