Unit 19 Learning Aim B
Worksheet A – Determining organic compound types from infrared spectra
For each of the following 7 spectra (for compounds A-G), describe the key features (i.e. the presence or absence of peaks for O-H, C-H,
C=O, C=C and C-O) and match each spectrum to one of the following 7 organic compound types:
• Alkane
•
• Alkene
• Alcohol Compound A demonstrates an alkene from the Infrared
• Ester spectra. The first rises are C-H stretches with the highest
• Carboxylic acid wave number at approximately 2900cm-1. A median
• Aldehyde sharp double carbon bond is also visible at around 1650
• Ketone cm-1 which is followed by a =C-H bend also known as a
stretching vibration which is the only stretch that is found
COMPOUND A below 3000 cm-1.
, • Compound B compound type is ketone
COMPOUND B • C-H stretch is found around 3100 – 2900
cm-1 .
• C=O peak of stretch at 1750 cm-1 and is
only present for aliphatic ketones
COMPOUND C
2
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
Worksheet A – Determining organic compound types from infrared spectra
For each of the following 7 spectra (for compounds A-G), describe the key features (i.e. the presence or absence of peaks for O-H, C-H,
C=O, C=C and C-O) and match each spectrum to one of the following 7 organic compound types:
• Alkane
•
• Alkene
• Alcohol Compound A demonstrates an alkene from the Infrared
• Ester spectra. The first rises are C-H stretches with the highest
• Carboxylic acid wave number at approximately 2900cm-1. A median
• Aldehyde sharp double carbon bond is also visible at around 1650
• Ketone cm-1 which is followed by a =C-H bend also known as a
stretching vibration which is the only stretch that is found
COMPOUND A below 3000 cm-1.
, • Compound B compound type is ketone
COMPOUND B • C-H stretch is found around 3100 – 2900
cm-1 .
• C=O peak of stretch at 1750 cm-1 and is
only present for aliphatic ketones
COMPOUND C
2
BTEC Assignment Brief v1.0
BTEC Internal Assessment QDAM January 2015
