Question

Waverumberom 11 INFRARED SPECTRUM Wenumber om a. CH3CH2OH B. CH3CHO C. CH3COCH3 d. CH3COOH e. CH3CH2NH,

Match the spectrum above with its correct matching letter

Answer 1

Basically IR spectrum provides the necessary information about the functional groups that are present in a molecule and thus from the above IR spectrum we can identify the molecules given below.

#1 IR spectra:

As the spectra show a doublet around 3300 cm^-1 it confirms the presence of two -N-H stretching of one -NH2 group and this is the signature peak for the primary amine group. -OH will give only 1 broad peak at 3300 cm^-1. Thus, this spectra is for: e. CH₃CH₂NH₂.

#2 IR spectra:

Here one signature peak is observable at 1715 cm^-1 which is attributed to the C=O stretching of a carbonyl group. Now, this carbonyl group is purely from the ketones. Acidic carbonyl appears at 1720 cm^-1. Thus, this spectra is for c. CH₃COCH₃.