Label each of the following substances as an acid, base, salt, or none of the above. Indicate whether the substance exists in aqueous solution entirely in molecular form, entirely as ions, or as a mixture of molecules and ions. (c) NaClO4
So for this example we're dealing with sodium perchlorate. We know that it's not an acid, since it doesn't begin with a hydrogen, it's not a base either because it's not a metal connected to OH. It is a salt, though, because it's ionic. We have sodium which is a metal connected to perchlorate which is a bunch of non-metals. So it's an ionic compound, and we're going to say that because it's a salt. Now based on our solubility rules, we're going to look at the sodium and say anything sodium is connected to is soluble, because sodium is in group IA, or we could look at the perchlorate and anything connected to perchlorate will also be soluble.
So this is a soluble ionic compound, therefore when it dissolves in a solution it will be ions. It will be just a mass of ions in the solution. So it would be, this breaking up into sodium, which is in group IA, so it's plus one, aqueous, because it's surrounded by water, and then perchlorate, which is ClO4 -1, aqueous again because those ions are surrounded by water.