Observe the sodium and chlorine atoms. Assuming that the inner rings are full of electrons, how many electrons are there total in each atom

See explanation

Explanation:

Chlorine has three shells. We know that the first shell contains two electrons, the other shell has eight electrons while the last shell has seven electrons. This means that chlorine has seventeen electrons.

For sodium, there are also three shells. The first shell has two electrons as usual. The next shell has eight electrons while the last shell has only one electron. This makes a total of eleven electrons for sodium.

4d^55s^1 ( third choice)