 What about something a bit more complex? Let's consider lithium nitrate. At the lab level, lithium nitrate, kind of like sodium chloride, looks like a white powder. At the molecular ionic level, I'm going to represent the lithium ions as yellow circles and the nitrate ions in O3- like this. If you draw the Lewis structure for a nitrate ion, you'll see that it has a nitrogen atom in the center and three oxygen atoms attached to that. So that's what this little three-petalled poppy flower thing represents. Remember that the bonds within a polyatomic ion like nitrate are covalent. Nitrogen and oxygen are both non-metals with high electronegativity. So when they bond to each other, they do it covalently by sharing electrons. So although nitrate is an ion, within that ion there are covalent bonds. It's a polyatomic ion. So lithium nitrate, like any ionic compound that has a polyatomic ion in it, is a sort of hybrid. Although the bonding between the lithium ions and the nitrate ions is ionic, there is also that covalent bonding within the polyatomic nitrate ions. So in the solid crystal of lithium nitrate, the ions are arranged alternately so that the positive lithium ions have maximum electrostatic attraction with the negative nitrate ions. Now when this solid is put into water, the water is able to break those ionic bonds, but not the covalent bonds. So this means the lithium ions and the nitrate ions separate and they spread through the water. However, the nitrate ions don't break up into nitrogen and oxygen atoms. The covalent bonds are not broken by the water. We write this at a symbolic level using an ionic equation like this. The right hand side of the equation represents the fact that the ions simply separate and dissolve in water. The polyatomic ion does not break up.