Orbital-Filling Diagrams

Orbital-Filling Diagram Example One: Carbon

Carbon has 6 electrons so it will have 6 arrows placed in its orbital-filling diagram. The order of adding the electrons to the various sublevels is 1s, 2s and 2p, with the lowest energy level first. For an element with enough electrons, the 3d sublevel would be filled after the 4s and before the 4p. Always fill the lowest energy level first when completing orbital-filling diagrams as in figure 11.

Orbital-Filling Diagram Example Two: Aluminum

 Aluminum has 13 electrons, so a completed orbital-filling diagram will have 13 arrows placed in it. In figure 12, the order of adding the electrons to the various sublevels is 1s, 2s, 2p, 3s and 3p.

Orbital-Filling Diagram Example Three: Bromine

Bromine has 35 electrons, so it will have 35 arrows placed in its orbital-filling diagram as in figure 13. The order bottom to top, adding the electrons  to the various sublevels, is 1s, 2s, 2p, 3s, 3p, 4s, 3d and 4p. Notice that the 3d sublevel is filled after the 4s and before the 4p. Remember, always fill the lowest energy  level first. This is consistent with the energy-shifted-electronic shell. Hund's Rule is demonstrated in the 4p sublevel.


© Pat Thayer 2014-2016