How do you identify the compound with IR spectrum with a molecular formula #C_5H_8O#?

1 Answer
Mar 5, 2016

The simple answer is YOU CAN'T.


#C_5H_8O# has 2 degrees of unsaturation. Each degree of unsaturation corresponds to a double bond or a ring. Could you draw ALL the isomers of #C_5H_8O# (there would be a dozen or so), and compare these to the known IR spectra of these isomers? It is possible, but it is much easier to make a few derivatives of your unknown species, and compare these melting points to melting points of the known derivatives.