Question

1) Identify the functional group (alkane, alkene, ketone, aldehyde, aldehyde, etc) for the compounds providing the IR spectra: % Transmittance 4000 3500 3000 1500 1000 500 2500 2000 Wavenumber(cm) % Transmittance 4000 3500 3000 1500 1000 500 2500 2000 Wavenumber(cm) % Transmittance 1000 3500 3000 1500 1000 500 2500 2000 Wavenumber (cm)

Answer 1

1 . IR -1 shows broad peak at 3400 cm-1 , for O-H stretching frequency

It also shows C-O stretching at C-O at 1100 cm-1 .

All the above data indicates presence of alcohol

Function group: Alcohol

2 . IR -1 shows two sharp peaks at 3400 cm-1 and 3500 cm-1 . , for NH2 symmetric and asymmetric stretching frequency

It also shows C-N stretching at 1600 cm-1 .

All the above data indicates presence of Primary amine

Function group: Primary amine

3 . IR -1 shows broad peak from 3500-2500 cm-1 , for O-H stretching of COOH frequency

It also shows C=O streching at 1700 cm-1 .

All the above data indicates presence of carboxylic acid

Function group: carboxylic acid