Question

The electronic configuration is given as:

$1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}3d^{10}4s^{2}4p^{6}4d^{10}5s^2$ is for:

• A. $f$-block element
• B. $d$-block element
• C. $p$-block element
• D. $s$-block element

Answer 1

Answer: (B)

$d$-block element

Electronic configuration is $1s^2,2s^2,2p^6,3s^2,2p^6,3d^{10},4s^2,4p^6,4d^{10},5s^2$.

Here last electron fills in $4d$-orbital so its $d$-block element.

Hence, option B is correct.