Question

Write the electronic configurations of the elements with the atomic numbers 61, 91, 101, and 109.

Answer 1

Atomic number	Electronic configuration
61	$[Xe]^{54}4f^55d^06s^2$
91	$[Rn]^{86}5f^26d^17s^2$
101	$[Rn]^{86}5f^{13}5d^07s^2$
109	$[Rn]^{86}5f^{14}6d^77s^2$