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Solutions for Lipids
20 Reagents in parts (a), (b), and (d) would react with alkenes. If both samples contained alkenes, these 
reagents could not distinguish the samples. Saponification (part (c)), however, is a reaction of an ester, so 
only the vegetable oil would react, not the hydrocarbon oil mixture. With saponification of a vegetable oil, 
as NaOH is consumed, the pH would gradually drop; with a petroleum oil, the pH would not change.
CO
CH
CH2
O
CH2
O
C
C
O
(CH2)7
O
(CH2)7
(CH2)12CH3
O
C
O
(CH2)7
C (CH2)12CH3
O
C (CH2)7
O
O
O
CH2
CH
CH2 O
CO
CH
CH2
O
CH2
O
C
C
O
(CH2)7
O
(CH2)7
(CH2)16CH3
O
CH CH(CH2)7CH3
CH CH(CH2)7CH3
CH CH(CH2)7CH3
CH CH(CH2)7CH3
CH CH(CH2)7CH3
CH CH(CH2)7CH3
21 (a) Add an aqueous solution of calcium ion or magnesium ion. Sodium stearate will produce a 
precipitate, while the sulfonate will not precipitate.
(b) Beeswax, an ester, can be saponified with NaOH. Paraffin wax is a solid mixture of alkanes and will 
not react.
(c) Myristic acid will dissolve (or be emulsified) in dilute aqueous base. Trimyristin will remain unaffected.
(d) Triolein (an unsaturated oil) will decolorize bromine in CCl4, but trimyristin (a saturated fat) will not.
22
(a)
(b)
asymmetric
carbon
*
optically active*
23
optically active
not optically active; symmetric
asymmetric
carbon
not optically active
(a)
C
O
(CH2)16CH3
C (CH2)16CH3
O
C (CH2)16CH3
O
O
O
CH2
CH
CH2 O
H2
Ni
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