Question

An atom has electronic configuration $1s^2,2s^{2}2p^6,3s^{2}3p^{6}3d^3,4s^2$, you will place it in which group : -

• A. fifth
• B. fifteenth
• C. second
• D. third

Answer 1

Answer: (A)

An atom has electronic configuration
$1s^2,2s^{2}2p^6,3s^{2}3p^{6}3d^3,4s^2$
It is a member of d-block element because the last
electron is filled in d-subshell as $3d^3$ and the
following electronic configuration is possible for
d-subshell as $(n-1)d^{1to10}$
Hence, it is member of fifth group.