Question

Among the following, the lowest degree of paramagnetism per mole of the compound at 298 K will be shown by:

• A. \( \text{MnSO}_4 \cdot 4\text{H}_2\text{O} \)
• B. \( \text{CuSO}_4 \cdot 5\text{H}_2\text{O} \)
• C. \( \text{FeSO}_4 \cdot 6\text{H}_2\text{O} \)
• D. \( \text{NiSO}_4 \cdot 6\text{H}_2\text{O} \)

Hint:

The degree of paramagnetism is determined by the number of unpaired electrons in the electron configuration.

Answer 1

The Correct Option is D

Step 1: Paramagnetism and electron configuration.
Paramagnetism is due to the presence of unpaired electrons. \( \text{Ni}^{2+} \) has a lower number of unpaired electrons compared to other metal ions in the given compounds, leading to the lowest paramagnetism.
Thus, the correct answer is (4).