The common valency shown by the elements of group 15 is/are

Options

A. `4`
B. `3,5`
C. `2,6`
D. `1,7`

Answer

To determine the common valency shown by the elements of Group 15, we need to analyze the electronic configurations and the bonding characteristics of these elements. The elements in Group 15 include Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb), and Bismuth (Bi).

### Step-by-Step Solution:

1. **Identify the Elements of Group 15**:
The elements are Nitrogen (N), Phosphorus (P), Arsenic (As), Antimony (Sb), and Bismuth (Bi).

2. **Determine the Electronic Configuration**:
- Nitrogen (N): 1s² 2s² 2p³
- Phosphorus (P): 1s² 2s² 2p⁶ 3s² 3p³
- Arsenic (As): 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p³
- Antimony (Sb): 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p⁶ 5s² 5p³
- Bismuth (Bi): 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 4p⁶ 5s² 5p⁶ 6s² 6p³

3. **Analyze the Valency**:
- **Nitrogen**: The outermost configuration is 2s² 2p³. Nitrogen can gain 3 electrons to complete its octet (achieving a -3 oxidation state) or lose 3 electrons to achieve a +3 oxidation state. Therefore, Nitrogen shows a common valency of +3.
- **Phosphorus**: The outermost configuration is 3s² 3p³. Phosphorus can also gain 3 electrons or can use its empty d-orbitals to expand its valency to +5. Thus, Phosphorus shows a common valency of +3 and +5.
- **Arsenic**: Similar to Phosphorus, Arsenic can exhibit +3 and +5 oxidation states.
- **Antimony**: Antimony can also exhibit +3 and +5 oxidation states.
- **Bismuth**: Bismuth typically shows +3 and +5 oxidation states.

4. **Conclusion**:
The common valencies shown by the elements of Group 15 are +3 and +5.

5. **Select the Correct Option**:
Based on the analysis, the correct answer is option 2: 3 and 5.