Answer:
1s^2 2s^2 2p^6 3s^1
Step-by-step explanation:
electron configuration of an element gives description of the distribution of electron in it's orbital of the atom, the superscript symbolize number of electron been hold by them.
The element here is sodium, which is a alkali metal
mass number =23
Number of proton= 11
electron must be seen in thelowest-energy subshell that is available in the the 3s orbital,
Hence, the electronic configuration is
1s^2 2s^2 2p^6 3s^1