I am little new to analytical chemistry, but after reading up on it, I realised that most analytical procedures need you to know what to test for beforehand.
May I know, given a sample of material G, is it possible to know its composition without knowing beforehand what to test for? ie. For a sample G, is there a procedure that can be followed so I can know that G has: 30% of compound X 20% of compound Y 50% of compound Z And that no other compounds exist in the sample. (But I do not know X, Y, Z are the compounds to test for beforehand.)
Or are all analytical chemistry procedures limited in the sense that you need to know what to test for first?
If yes, what is the closest possible procedure to follow to get what I want as outlined above?
Lastly, are analytical chemistry procedures also limited in the sense that you can never know for sure if that "no other compounds exist"?