Which one of the followign is the most basic ?

Options

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

Answer

To determine which of the given halogens (Iodine, Bromine, Chlorine, and Fluorine) is the most basic, we need to analyze their electronegativity and how it relates to their basicity.

### Step-by-Step Solution:

1. **Understanding Basicity**: Basicity refers to the ability of an atom to donate a lone pair of electrons. The more readily an atom can donate its electrons, the more basic it is.

2. **Electronegativity of Halogens**: The halogens have varying electronegativities, which is a measure of an atom's ability to attract and hold onto electrons. The order of electronegativity for the halogens is:
- Fluorine (F) > Chlorine (Cl) > Bromine (Br) > Iodine (I)

3. **Relationship Between Electronegativity and Basicity**: There is an inverse relationship between electronegativity and basicity. This means that as electronegativity increases, basicity decreases. Highly electronegative elements are less likely to donate their electrons because they tend to attract electrons instead.

4. **Analyzing Each Halogen**:
- **Fluorine (F)**: Highly electronegative, therefore it does not donate electrons easily and is not basic.
- **Chlorine (Cl)**: Less electronegative than fluorine but still relatively high, thus it is less basic than bromine and iodine.
- **Bromine (Br)**: Less electronegative than chlorine, so it is more basic than chlorine.
- **Iodine (I)**: The least electronegative of the four, making it the most basic as it can easily donate its lone pair of electrons.

5. **Conclusion**: Based on the analysis, Iodine (I) is the most basic among the given options.

### Final Answer: Iodine (I) is the most basic.

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