Mark the correct statements about halogens.

Options

A. Electron affinity of halogens is in the order `F gt Clgt Brgt I`.
B. HF is the strongest hydrohalic acid.
C. `F_(2)` has lower bond dissociation energy than `Cl_(2)`
D. All halogens show variable oxidation states.

Explanation

To determine the correct statements about halogens, let's analyze each option one by one.

**Step 1: Analyze Option 1**
- The statement claims that the electron affinity of halogens is in the order: F > Cl > Br > I.
- However, the correct order of electron affinity is actually Cl > F > Br > I. Chlorine has the highest electron affinity due to its larger atomic size compared to fluorine, which makes it easier for chlorine to accept an electron.
- **Conclusion**: Option 1 is incorrect.

**Step 2: Analyze Option 2**
- The statement claims that HF is the strongest hydrohalic acid.
- HF is not the strongest hydrohalic acid; in fact, it is one of the weakest due to hydrogen bonding between HF molecules, which makes it difficult for HF to release H+ ions into solution.
- **Conclusion**: Option 2 is incorrect.

**Step 3: Analyze Option 3**
- The statement claims that F2 has lower bond dissociation energy than Cl2.
- This statement is correct. The bond in F2 is weaker due to inter-electronic repulsion between the lone pairs of the small fluorine atoms, which makes the bond easier to break compared to Cl2, where such repulsion is less significant.
- **Conclusion**: Option 3 is correct.

**Step 4: Analyze Option 4**
- The statement claims that all halogens show variable oxidation states.
- This is misleading. While halogens can exhibit different oxidation states, they predominantly exhibit a single oxidation state of -1 in most compounds.
- **Conclusion**: Option 4 is incorrect.

**Final Conclusion**: The only correct statement is Option 3: F2 has lower bond dissociation energy than Cl2.