Start by drawing the diagonal arrows through the diagram as shown. The
order of filling can be charted by following each arrow from tail to head and then
to the tail of the next one. In this way you get the same order of filling as is shown
in Figure 9 and Table 3:
1 s^2 2 s^2 2 p^6 3 s^2 3 p^6 4 s^2 3 d^10 4 p^6 5 s^2 4 d^10 5 p^6 6 s^2 4 f^14 5 d^10 6 p^6 7 s^2Lewis Structures (Electron Dot Notation)
In 1916 G. N. Lewis devised the electron dot notation, which may be used in
place of the electron configuration notation. The electron dot notation shows only
the chemical symbol surrounded by dots to represent the electrons in the
incomplete outer level. Examples are:
The symbol denotes the nucleus and all electrons except the valence
electrons. The dots are arranged at the four sides of the symbol and are paired
when appropriate. In the examples above, the depicted electrons are the valence
electrons found in the outer energy level orbitals.
4 s^1 is shown for potassium (K)
4 s^2 4 p^3 are shown for arsenic (As)
5 s^2 is shown for strontium (Sr)
5 s^2 5 p^5 are shown for iodine (I)
6 s^2 6 p^6 are shown for radon (Rn)