Problems and exercisesFunctional Groups

1. Recognize the functional groups

Identify and name the functional groups in these well-known molecules:

2. Classify

a) State whether each alcohol is primary, secondary or tertiary:

1. CH₃CH₂OH
2. (CH₃)₂CHOH
3. (CH₃)₃COH

b) State whether each amine is primary, secondary or tertiary:

1. CH₃CH₂NH₂
2. CH₃CH₂NHCH₃
3. CH₃CH₂N(CH₃)₂

c) Which functional group does each compound in these closely related pairs have?

1. CH₃COOH  /  CH₃COOCH₃
2. CH₃CH₂CHO  /  CH₃COCH₃
3. CH₃CONH₂  /  CH₃CH₂NH₂

3. Which is the main function?

These molecules have two functional groups. Apply the order of precedence given in the theory to decide which one is the main function (which gives the suffix of the name) and which one is named as a prefix. Name them.

1. HOCH₂CH₂COOH
2. CH₃COCH₂CH₂NH₂
3. HOCH₂CH₂CHO
4. H₂NCH₂COOH

4. From name to structure and back

a) Write the formula of these compounds:

1. ethyl ethanoate (ethyl acetate)
2. N-methylethanamide
3. but-3-en-2-ol
4. 4-hydroxybenzaldehyde

b) Name these compounds:

1. CH₃CH₂CH₂COOCH₃
2. CH₃CH₂OCH₂CH₃
3. (CH₃)₂CHCOOH
4. CH₃CH₂CH(NH₂)CH₃

5. Same formula, different function

Write compounds with each of these molecular formulas that have different functional groups:

C₂H₆O  ·  C₃H₆O  ·  C₃H₆O₂

6. Everyday chemistry

Match each product with the compound responsible and its functional group: