Which of the following halogen always show only one oxidation state -

Options

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

Answer

To determine which halogen always shows only one oxidation state, we can follow these steps:

### Step 1: Identify the Halogens
The halogens are a group of elements in Group 17 of the periodic table, which include:
- Fluorine (F)
- Chlorine (Cl)
- Bromine (Br)
- Iodine (I)
- Astatine (At)

### Step 2: Understand Oxidation States of Halogens
Halogens can exhibit various oxidation states. However, we need to identify which halogen has a fixed oxidation state:
- **Fluorine (F)**: Always has an oxidation state of -1.
- **Chlorine (Cl)**: Can have oxidation states of -1, +1, +3, +5, and +7.
- **Bromine (Br)**: Can have oxidation states of -1, +1, +3, +5, and +7.
- **Iodine (I)**: Can have oxidation states of -1, +1, +3, +5, and +7.
- **Astatine (At)**: Can also exhibit multiple oxidation states.

### Step 3: Conclusion
From the analysis, we find that:
- **Fluorine (F)** is the only halogen that consistently shows only one oxidation state, which is -1.

Thus, the correct answer to the question is **Fluorine (F)**.

### Final Answer
The halogen that always shows only one oxidation state is **Fluorine (F)**.

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