If ir does not give you the exact formula of a chemical

Question

1. If IR does not give you the exact formula of a chemical compound, what useful information does it provide?
2. In the Determination of Vitamin C lab, identify what would change in the IR spectra of DCPIP after it is reduced? What characteristic IR bands will be present before it is reduced and after?
3. In the Determination of Vitamin C lab, when Vitamin C is oxidized, what do you expect to happen to the IR spectrum? In other words, what changes will you look for to verify that Vitamin C has been oxidized?
4. In the Synthesis of Aspirin lab, describe how the IR spectra changes from the reactants to the products. Do not include water as one of the products. Assume that the aspirin has been separated from the water when you obtain the IR.
5. In the Saponification lab, describe how the IR spectra would be different for Tristearin and for glycerol.
6. In the Project you designed in Module 2, you had three compounds you were separating using column chromatography. If after you performed your column, you obtained the IR spectra of the samples from the column, what characteristic IR bands would you look for to identify the three compounds. (Use the IUPAC name for the three compounds as you give the answer to this question.)