JEE Mains · Chemistry · STD 12 - 4. d and f- block elements
The number of \(4 f\) electrons in the ground state electronic configuration of \(\mathrm{Gd}^{2+}\) is ........ . [Atomic number of \(\mathrm{Gd}=64\) ]
- A \(7\)
- B \(6\)
- C \(1\)
- D \(8\)
Answer & Solution
Correct Answer
(A) \(7\)
Step-by-step Solution
Detailed explanation
The electronic configuration of \({ }_{64} \mathrm{Gd}:[\mathrm{Xe}] 4 \mathrm{f}^{7} 5 \mathrm{~d}^{1} 6 \mathrm{~s}^{2}\) So the electronic configuration of \({ }_{64} \mathrm{Gd}^{2+}:[\mathrm{Xe}] 4 \mathrm{f}^{7} 5 \mathrm{~d}^{1} 6 \mathrm{~s}^{0}\) \(i.e.\) the number of…
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