Complete the table about lipids.\

Kind of Lipid	Description
	Each carbon atom in a lipid's fatty acid chain is joined to another carbon atom by a single bond.
Unsaturated
	A lipid's fatty acids contain more than one double bond.

Lithium chloride has a solubility of 55 g of LiCl in 100 g of $\mathrm{H_2O}$ at 25 $\degree$C. Determine if adding 75 g of LiCl to 150. g of $\mathrm{H_2O}$ mixtures forms an unsaturated or saturated solution at 25 $\degree$C.

Potassium fluoride has a solubility of 92 g of KF in 100 g of $\mathrm{H_2O}$ at 18 $\degree$C. Determine if adding 35 g of KF to 25 g of $\mathrm{H_2O}$ mixtures forms an unsaturated or saturated solution at 18 $\degree$C.

Potassium chloride has a solubility of 43 g of KCl in 100 g of H2O at 50 $\degree$ C. Determine if adding 15 g of KCl to 25 g of $\mathrm{H_2O}$ forms an unsaturated or saturated solution at 50 $\degree$ C.

Indicate whether each of the following descriptions concerning the molecule sphingosine is true or false.

a. Four functional groups are present.

b. The carbon chain is unsaturated.

c. It has a head-and-two-tails structure.

d. An amino functional group is present.

With the help of Figure 17.8, indicate whether the ring system in each of the following heterocyclic amines is (1) saturated (2) unsaturated or (3) fused. More than one choice may be correct for a given heterocyclic amine.

a. Pyrrole

b. Indole

c. Pyrimidine

d. Purine

Which of the following processes are spontaneous, and which are nonspontaneous? (a) Freezing of water at $2^{\circ} \mathrm{C}$ (b) Corrosion of iron metal (c) Expansion of a gas to fill the available volume (d) Separation of an unsaturated aqueous solution of potassium chloride into solid $\mathrm{KCl}$ and liquid water

Potassium fluoride has a solubility of 92 g of KF in 100 g of $\mathrm{H_2O}$ at 18 $\degree$C. Determine if adding 145 g of KF to 150. g of $\mathrm{H_2O}$ mixtures forms an unsaturated or saturated solution at 18$\degree$C.

What type of lipid does not contain fatty acid chains? Why are these molecules classified as lipids?

By name or formula, give one example of each of the following types of compounds:
(a) aromatic nitro compound;
(b) aliphatic amine;
(c) chlorophenol;
(d) aliphatic diol;
(e) unsaturated aliphatic alcohol;
(f) alicyclic ketone;
(g) halogenated alkane;
(h) aromatic dicarboxylic acid.

Potassium chloride has a solubility of 43 g of $\mathrm{KCl}$ in 100 g of $\mathrm{H_2O}$ at 50 $\dedgree$C. Determine if adding 86 g of $\mathrm{KCl}$ to 150. g of $\mathrm{H_2O}$ forms an unsaturated or saturated solution at 50 $\dedgree$C.

Label each of the following molecules as saturated or unsaturated.

(a) $\mathrm{CH}_3 \mathrm{CH}_2 \mathrm{CHCH}_2$

(b) $\mathrm{C}_3 \mathrm{H}_6$

(c) CCC(C)C

Classify each of the following types of lipids as (1) an energy-storage lipid (2) a membrane lipid (3) an emulsification lipid or (4) a messenger lipid.

a. Bile acids b. Cholesterol c. Eicosanoids d. Sphingophospholipids

Winter wheat is planted in the early fall, grows over the winter when the weather is colder, and is harvested in the spring. As the temperature drops, the makeup of the plasma membrane of winter wheat changes. Unsaturated fatty acids replace saturated fatty acids in the phospholipids of the membrane. Why is this a suitable adaptation?