Chapter 2, Problem 4FIO

Figure 2.17 Fatty acids.

Double bonds in the tails are highlighted in red.

1. A. The tail of stearic acid is fully saturated with hydrogen atoms.
2. B. Linoleic acid, with two double bonds, is unsaturated. The first double bond occurs at the sixth carbon from the end of the tail, so linoleic acid is called an omega-6 fatty acid. Omega-6 and
3. C. omega-3 fatty acids are “essential fatty acids,” which means your body does not make them and they must come from food.
4. D. The hydrogen atoms around the double bond in oleic acid are on the same side of the tail. Most other naturally occurring unsaturated fatty acids have these cis bonds.
5. E. Hydrogenation creates abundant trans bonds, with hydrogen atoms on opposite sides of the tail.

Figure It Out: Are the double bonds in linolenic acid cis or trans?