Which of the following is most electronegative

Options

A. O
B. S
C. Te
D. Se

Explanation

To determine which of the given elements is the most electronegative, we can follow these steps:

### Step-by-Step Solution

1. **Identify the Elements**: The elements mentioned are Oxygen (O), Sulfur (S), and possibly others from the oxygen family (Group 16), which includes Selenium (Se) and Tellurium (Te).

2. **Understand Electronegativity**: Electronegativity is a measure of an atom's ability to attract and hold onto electrons. It generally increases across a period (from left to right) and decreases down a group (from top to bottom) in the periodic table.

3. **List the Atomic Numbers**:
- Oxygen (O) has an atomic number of 8.
- Sulfur (S) has an atomic number of 16.
- Selenium (Se) has an atomic number of 34.
- Tellurium (Te) has an atomic number of 52.

4. **Analyze the Trend**: As we move down the group from Oxygen to Sulfur to Selenium to Tellurium, the atomic radius increases, which leads to a decrease in electronegativity. This is because the increased distance between the nucleus and the valence electrons reduces the nucleus's ability to attract electrons.

5. **Compare Electronegativity Values**:
- The electronegativity values (on the Pauling scale) are approximately:
- Oxygen: 3.44
- Sulfur: 2.58
- Selenium: 2.55
- Tellurium: 2.1

6. **Conclusion**: Based on the electronegativity values, Oxygen is the most electronegative element among the ones listed.

### Final Answer
**Oxygen (O) is the most electronegative element.**

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