Question

in the stoichiometry lab, students performed a saponification lab using excess sodium hydroxide with either palmitin or stearin. using the information from the lab, select the incorrect description below. soaps are salts of carboxylic acids that contain many carbon atoms in a long hydrocarbon chain. soaps are prepared through the base hydrolysis (saponification) of a triglyceride. the ionic carboxylate end is soluble in nonpolar substances; whereas the long nonpolar hydrocarbon chain is soluble in water. soap micelles form in aqueous solutions.

Explanation:

• Analyze each option:
• Option 1: Soaps are salts of long - chain carboxylic acids (containing many C atoms), so this is correct.
• Option 2: Saponification (base hydrolysis of triglycerides) is the method to prepare soaps, so this is correct.
• Option 3: The ionic carboxylate end is polar and soluble in polar substances like water, while the nonpolar hydrocarbon chain is soluble in nonpolar substances. So the description here is incorrect.
• Option 4: Soap micelles do form in aqueous solutions (the nonpolar tails cluster inside, polar heads outside), so this is correct.

Answer:

The ionic carboxylate end is soluble in nonpolar substances; whereas the long nonpolar hydrocarbon chain is soluble in water.