Question

The electronic configuration of the element which is just above the element with atomic number $43$ in the same periodic group is:

• A. $1s^2,2s^2,2p^6,3s^2,3p^{6}3d^5,4s^2$
• B. $1s^2,2s^2,2p^6,3s^2,3p^{6}3d^{10},4s^{2}4p^5$
• C. $1s^{2}2s^{2}2p^6,3s^{2}3p^{6}3d^6,4s^1$
• D. $1s^2,2s^2,2p^6,3s^{2}3d^{10},4s^{1}4p^6$

Answer 1

Answer: (A)

$1s^2,2s^2,2p^6,3s^2,3p^{6}3d^5,4s^2$

The atomic number of the element above the element number 43 is: $43-18=25$

The electronic configuration of the element with $Z=25$ is $1s^2,2s^2,2p^6,3s^2,3p^{6}3d^5,4s^2$.