Question

what is the last portion of the electron configuration for gallium, ga?
$4d^{11}$
$4p^{1}$
$4d^{11}$
$3p^{1}$

Explanation:

Gallium (Ga) has an atomic number of 31. Its full electron configuration is $1s^22s^22p^63s^23p^64s^23d^{10}4p^1$. The last portion refers to the highest energy subshell that gets filled last, which is the $4p$ orbital with 1 electron.

Answer:

4p¹