1. Chapter 14 Aldehydes, Ketones, and Chiral Molecules
14.2 Physical Properties of Aldehydes and Ketones

2. Polar Carbonyl Group The polar carbonyl group
provides dipole–dipole interactions
does not have H on the oxygen atom
cannot form hydrogen bonds

3. Boiling Points Aldehydes and ketones have polar carbonyl groups (C═O)
attractions between polar groups
higher boiling points than alkanes and ethers of similar mass
lower boiling points than alcohols of similar mass

4. Comparison of Boiling Points

5. Comparison of Physical Properties

6. Learning Check Select the compound in each pair that would have the
higher boiling point. Explain.
A. CH3—CH2—CH3 or CH3—CH2—OH
B or
C. CH3—CH2—OH or CH3—O—CH3

7. Solution Select the compound in each pair that would have the
higher boiling point. Explain.
A. CH3—CH2—OH An alcohol forms hydrogen bonds.
B There are dipole–dipole attractions between the carbonyl groups
C. CH3—CH2—OH An alcohol forms hydrogen bonds, but an ether does not.

8. Solubility in Water Aldehydes and ketones are soluble in water
have electronegative O atoms in their carbonyl groups that form hydrogen bonds with water

9. Learning Check
Indicate if each of the following is or is not soluble in
water:
A. CH3—CH2—CH3
B. CH3—CH2—OH C. D.

10. Solution Indicate if each of the following is or is not soluble in
water:
A. CH3—CH2—CH3
B. CH3—CH2—OH C. D.
not soluble in water
soluble in water
soluble in water
soluble in water