MCQ
Which of the following is paramagnetic
- ✓$N{i^{ + 2 }}$
- B$C{u^ + }$
- C$Z{n^{ + 2 }}$
- D$S{c^{ + 3 }}$
✓
Answer
Correct option: A.
$N{i^{ + 2 }}$
a
(a) Elements or ions containing unpaired electrons are paramagnetic.
(a) Elements or ions containing unpaired electrons are paramagnetic.
$_{28}Ni = [Ar]\;3{d^8}4s_2^{}$ ; $N{i^{2 + }} = [Ar]\;3{d^8}4{s^0}$
Because $N{i^{2 + }}$ have $2$ unpaired electrons in $3d$ subshell therefore it is paramagnetic.
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