Which gives the more concentrated solution, stearic acid

Solution 5P:

Here, we are going to explain the more concentrated stearic acid solution whether in (a) H2O or (b) CCl4.

Step 1: (a)

The carboxylic acids with general formula CH3(CH2)nCOOH have both polar and nonpolar ends. Therefore, it can form Hydrogen bonds with the polar -OH group. Thus, it can be exchangeable with the H-bonds of water molecules which soluble the acid in water.

When the size of the nonpolar hydrocarbon chain increases, it undergoes dipole induced dipole interactions with water molecules It reduces the formation of hydrogen bond. Therefore, the carboxylic acid molecules cannot replace the hydrogen bonds with water molecules. Thus, carboxylic acid  become insoluble in water.

Therefore, with the increase in n, the solubility of carboxylic acids in water decreases.

Therefore, stearic acid in H2O will not give the more concentrated solution.