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.

$_{28}Ni = [Ar]\;3{d^8}4s_2^{}$ ; $N{i^{2 + }} = [Ar]\;3{d^8}4{s^0}$

Because $N{i^{2 + }}$ have $2$  unpaired electrons in $3d$  subshell therefore it is paramagnetic.

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