What is the difference between the outer shell of sodium and the outer shell of fluorine?

The outer shell (the outermost shell) of Na there is 1 electron while in F there are 7 electrons

Given

Sodium and Fluorine

Required

The outer shell difference

Solution

Sodium (symbol Na) is an element in group 1 (alkaline) which has the atomic number 11

So the electron configuration is: [Ne] 3s¹

Meanwhile, Fluorine (symbol F) is a halogen element (group 17) which has atomic number 9

So the electron configuration is: [He] 2s² 2p⁵

If we look at the electron configurations of these two elements, it shows that the element Na to achieve its stability will release 1 electron in the outer shell so that it has an electron configuration like Ne

Meanwhile, Fluorine will need 1 more electron so it can be stable like Ne

So in the outer shell of Na there is 1 electron while in F there are 7 electrons