Question

23 what is the correct electron configuration for a ground - state atom with 7 electrons? * (0.5 points) a. 1s^2 2s^2 2p^3 b. 1s^2 2s^2 2p^2 3s^1 c. 1s^2 2s^3 2p^2 d. 1s^2 2s^5

Explanation:

Step1: Recall electron - filling order

Electrons fill orbitals in the order 1s, 2s, 2p, 3s, 3p, etc. The s - orbital can hold a maximum of 2 electrons and the p - orbital can hold a maximum of 6 electrons.

Step2: Fill 7 electrons

The first 2 electrons go into the 1s orbital (1s²). The next 2 electrons go into the 2s orbital (2s²). Then we have 3 remaining electrons which go into the 2p orbital (2p³). So the electron configuration is 1s²2s²2p³.

Answer:

A. 1s²2s²2p³