Question

The atomic number of $Ni$ and $Cu$ are $28$ and $29$ respectively. The electronic configuration $ 1s^{2},\,\,2s^{2},\,\,2p^{6},\,\,3s^{2}\,\,3p^{6}\,\,3d^{10}$ represents

• A. $ Cu^{+}$
• B. $Cu^{2+}$
• C. $ Ni^{2+}$
• D. $ Ni $

Answer 1

Answer: (A)

Electronic configuration of
${}_{28} Ni =1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{8}, 4 s^{2} $
$ Ni ^{2+} =1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{8}, 4 s^{0} $
${ }_{29} Cu =1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{10}, 4 s^{1} $
$Cu ^{+} =1 s^{2}, 2 s^{2} 2 p^{6}, 3 s^{2} 3 p^{6} 3 d^{10}, 4 s^{0}$
So, the given configuration is of $Cu ^{+}$.