The halogen which can form both contions and anions also

Options

A. F
B. Cl
C. Br
D. I

Answer

To determine which halogen can form both cations and anions, we can analyze the properties of the halogens: fluorine (F), chlorine (Cl), bromine (Br), and iodine (I).

### Step-by-Step Solution:

1. **Identify the Halogens**: The halogens in the periodic table are fluorine (F), chlorine (Cl), bromine (Br), and iodine (I).

2. **Understand the Formation of Anions**: Halogens typically gain an electron to form anions. For example:
- Fluorine forms fluoride ions (F⁻).
- Chlorine forms chloride ions (Cl⁻).
- Bromine forms bromide ions (Br⁻).
- Iodine forms iodide ions (I⁻).

3. **Understand the Formation of Cations**: While halogens primarily form anions, some can also form cations under specific conditions.
- Iodine (I) can form a cation known as the triiodide ion (I₃⁻) when it reacts with itself, but it can also exist in a positive oxidation state as I⁺ or I₃⁺ in certain compounds.

4. **Evaluate Each Halogen**:
- **Fluorine (F)**: Only forms anions (F⁻).
- **Chlorine (Cl)**: Only forms anions (Cl⁻).
- **Bromine (Br)**: Only forms anions (Br⁻).
- **Iodine (I)**: Can form both anions (I⁻) and cations (like I₃⁺).

5. **Conclusion**: The halogen that can form both cations and anions is **iodine (I)**.

### Final Answer:
The halogen which can form both cations and anions is **iodine (I)**.

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