What are the constituent units of Iodine?

What are the constituent units of sodium chloride.

What type of bonding would you expect between magnesium and chlorine in magnesium chloride.

What type of bonding would you expect between two hydrogen atoms in a molecule of hydrogen.

Draw electron dot diagrams to depict the formation of:

Magnesium oxide from ${}_{12}\mathrm{Mg}^{24}$ and ${}_8\mathrm{O}^{16}$

Draw electron dot diagram to depict the formation of molecule of chlorine from two atoms of ${}_{17}\mathrm{Cl}^{35}$.