The bonding in the pure second-row elements is shown across the top of this page. The next chapter will be concerned with covalent bonds between atoms of similar electronegativities. Chapter 5 will be devoted to ionic bonds between atoms of quite different electronegativities.

The second electron shell is not the end of the road for atom building.

In Chapter 6 we will see a third electron shell, again capable of holding eight outer electrons. Elements of atomic number 11 through 18 show chemical properties very similar to elements 3 through 10. This is because these two sets of elements have corresponding numbers of outer electrons. It is these outer electrons that react with other atoms, thus giving each atom its distinctive chemical properties.