Question

What do you know about a chemical compound by looking at its chemical formula?

Answer 1

You are given precise information about its chemical composition, and usually what type of compound it is, i.e. molecular or ionic.

Explanation:

So let's take a few formula, `NaCl`, `CH_4`, `FeSO_4`. All of these are real compounds; sodium chloride and ferrous sulfate are ionic, and methane is molecular. The formula does not tell you this, it gives you the chemical composition, and you have to know by experiment how it behaves.

`NaCl`, and `FeSO_4` are binary salts of `Na^+`, `Cl^-`, `Fe^(2+)`, and `SO_4^(2-)`. The iron salts are a good example because we could also have `"ferric sulfate"`, i.e. `Fe_2(SO_4)_3`, which gives `2xxFe^(3+)`, and `3xxSO_4^(2-)`.

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.