a. The “octet rule” in chemistry helps predict the types of bonds that atoms will form. In general, an atom will be most stable if it fills its outer shell of 8 electrons. Atoms with fewer than 4 valence electrons tend to donate electrons and those with more than 4 valence electrons tend to accept additional electrons; those with exactly 4 can do both. Using this rule, determine what category each of the following elements falls into: N, S, C, P, O, H, Ca, Fe, and Mg. (You will need to work out the valence of the atoms.)

b. Make simple drawings to show how atoms such as N and Cl form diatomic molecules.

c. What type of chemical reaction is occurring between Na and Cl2?