What do you know about a chemical compound by looking at its chemical formula?
You are given precise information about its chemical composition, and usually what type of compound it is, i.e. molecular or ionic.
So let's take a few formula,
On the other hand, if you are quoted a formula containing only carbon, hydrogen, nitrogen, and oxygen, you gots an organic compound, that is possibly NOT going to be water soluble. If I have missed the point of your enquiry then come back for another serve.