Question

Which of the following statements(s) is (are) correct?

• A. The electronic configuration of Cr (at. no: 24) is $\left[Ar\right]3d^{5} 4S^{1}$
• B. The magnetic quantum number may have a negative value
• C. In Ag (at. no: 47), 23 electrons have spins of one type and 24 electrons have spins of opposite type
• D. The oxidation state of nitrogen in $HN_{3}$ is - 3

Answer 1

Answer: (C)

In Ag (at. no: 47), 23 electrons have spins of one type and 24 electrons have spins of opposite type

Answer 2

Electronic configuration of $Cr\to\left[Ar\right]3d^{5} 4S^{1}$
$\to$ Let l = 1, $m_{1}$ = -1, 0, +1
$\to Ag\to1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10} 4s^{2}4p^{6}4d^{10}5s^{1}$
No. of electrons having $m_{s} =+1/2 \, or-1/2 =$ 24 and rest 23
$\to$ oxidation number of N in $\,HN_{3} in -\frac{1}{3}$