Which of the following elements will gain one electron more readily comparison to other elements of their groups? a)`S(g)` B)`Na(g)` C)`O(g)` D)`CI(g)`

Options

A. S(g)
B. Na(g)
C. O(g)
D. Cl (g)

Explanation

To determine which of the given elements will gain one electron more readily compared to the other elements in their respective groups, we will analyze each option based on their electronic configurations and tendencies to gain electrons.

### Step 1: Analyze Each Element
1. **S (Sulfur)**:
- Atomic number: 16
- Electronic configuration: 2, 8, 6
- Sulfur is in group 16 (chalcogens) and tends to gain 2 electrons to achieve a stable octet. However, it is less electronegative than oxygen.

2. **Na (Sodium)**:
- Atomic number: 11
- Electronic configuration: 2, 8, 1
- Sodium is a metal in group 1 (alkali metals) and has a tendency to lose its one valence electron rather than gain one. Thus, it can be eliminated from consideration.

3. **O (Oxygen)**:
- Atomic number: 8
- Electronic configuration: 2, 6
- Oxygen is highly electronegative and tends to gain 2 electrons to complete its octet. However, due to its small size, it experiences significant repulsion when trying to gain an additional electron.

4. **Cl (Chlorine)**:
- Atomic number: 17
- Electronic configuration: 2, 8, 7
- Chlorine is in group 17 (halogens) and has a strong tendency to gain 1 electron to achieve a stable octet. It is less electronegative than fluorine, which allows it to gain an electron more easily.

### Step 2: Compare the Elements
- **Sodium (Na)** is eliminated as it loses electrons.
- **Oxygen (O)**, while electronegative, has a small size that creates repulsion when gaining electrons, making it less favorable for gaining an additional electron.
- **Sulfur (S)** has a greater tendency to gain an electron compared to oxygen due to its larger size, which reduces electron-electron repulsion.
- **Chlorine (Cl)**, although it is less electronegative than fluorine, has a high tendency to gain an electron due to its larger size compared to fluorine, which also reduces repulsion.

### Conclusion
Based on the analysis, the elements that will gain one electron more readily compared to the other elements in their groups are:
- **Sulfur (S)**
- **Chlorine (Cl)**

Thus, the correct options are **C (O)** and **D (Cl)**.

### Final Answer
**C (O)** and **D (Cl)** are the elements that will gain one electron more readily compared to the other elements of their groups.

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