What is a functional group? Name the functional group and give the IUPAC name of the two-carbon compound in each of these classes: alcohol, aldehyde and carboxylic acid.
How to lay out the answer. Follow the frame, then write it in your own words.
1 · Define. A functional group is an atom or group of atoms that gives a compound its typical properties.
2 · Alcohol. Group -OH (hydroxyl): CH₃CH₂OH, ethanol.
3 · Aldehyde. Group -CHO: CH₃CHO, ethanal.
4 · Carboxylic acid. Group -COOH (carboxyl): CH₃COOH, ethanoic acid.
5 · Close in one line. So the word root shows the number of carbons and the ending shows the functional group.
Scoring tip: Count the carbon inside -CHO and -COOH when you choose the word root. Missing it is the commonest naming mistake.
