Electronegativity of F is larger than that of Cl but electron gain enthalpy of Cl is larger than of F. (T/F)

Answer

To determine whether the statement "Electronegativity of F is larger than that of Cl but electron gain enthalpy of Cl is larger than of F" is true or false, we can analyze the definitions and properties of electronegativity and electron gain enthalpy.

### Step-by-Step Solution:

1. **Understanding Electronegativity**:
- Electronegativity is defined as the tendency of an atom to attract shared electrons in a chemical bond.
- Fluorine (F) has a higher electronegativity than chlorine (Cl) because it is smaller in size and has a stronger effective nuclear charge that attracts the bonding electrons more effectively.

2. **Understanding Electron Gain Enthalpy**:
- Electron gain enthalpy is the amount of energy released when an electron is added to an atom in the gaseous state.
- Chlorine (Cl) has a larger electron gain enthalpy than fluorine (F) because it is larger in size, and the added electron experiences less repulsion from the nucleus compared to fluorine, where the added electron is closer to the nucleus and experiences more repulsion.

3. **Comparison of Electronegativity**:
- The atomic number of fluorine is 9, with an electronic configuration of 1s² 2s² 2p⁵.
- The atomic number of chlorine is 17, with an electronic configuration of 1s² 2s² 2p⁶ 3s² 3p⁵.
- Since fluorine has its outer electrons in the 2p subshell, which is closer to the nucleus than chlorine's 3p subshell, fluorine has a higher electronegativity.

4. **Comparison of Electron Gain Enthalpy**:
- When considering the electron gain enthalpy, chlorine's larger atomic size means that the added electron experiences less repulsion and is more stable in the 3p subshell than in fluorine's 2p subshell.
- Therefore, chlorine has a more negative (larger in magnitude) electron gain enthalpy compared to fluorine.

5. **Conclusion**:
- The statement claims that the electronegativity of F is larger than that of Cl (True) and that the electron gain enthalpy of Cl is larger than that of F (True).
- Therefore, the overall statement is **True**.

### Final Answer:
The statement is **True**.