Question

1. Write an equation for the base hydrolysis of methyl benzoate by KOH.

2. How many ester groups are in a triglyceride? Give the structure of a triglyceride (triacylglycerol) from you textbook or the lab sheet and put a box around each ester group.

3. If the triglyceride in question 2 underwent base hydrolysis, what 4 products would you obtain? Give the condensed formulas.

4. Which of these products are soaps? (you may circle the ones that are soaps.)

Answer 1

Answer 2

1. The equation for the base hydrolysis of methyl benzoate by KOH is as follows: Methyl benzoate + KOH → Benzoate ion + Methanol + K+ + H2O

2. A triglyceride consists of a glycerol molecule bonded to three fatty acid molecules. Each fatty acid molecule is connected to the glycerol molecule through an ester linkage. Here is the structure of a triglyceride with the ester groups boxed:

   mathematicaCopy code     Box          Box          Box|                   |                  |

   -O-C-R -O-C-R -O-C-R | | | -O-C-R -O-C-R -O-C-R | | | Glycerol Glycerol Glycerol

3. When the triglyceride undergoes base hydrolysis, it breaks down into glycerol and three fatty acid salts (carboxylate ions). The four products obtained are:

• Glycerol (unchanged)

• Fatty acid salt 1 (carboxylate ion 1)

• Fatty acid salt 2 (carboxylate ion 2)

• Fatty acid salt 3 (carboxylate ion 3)

The condensed formulas of the products depend on the specific fatty acids present in the triglyceride. For example, if the fatty acids are stearic acid (C18:0), palmitic acid (C16:0), and oleic acid (C18:1), the condensed formulas would be:

• Glycerol (unchanged)

• Stearate ion (C18:0)

• Palmitate ion (C16:0)

• Oleate ion (C18:1)

4. The fatty acid salts (carboxylate ions) obtained in the hydrolysis process can act as soaps. Soap molecules have a polar end (carboxylate ion) and a non-polar end (hydrocarbon chain). They can form micelles in water, allowing the removal of dirt and oil from surfaces. Therefore, the fatty acid salts produced in the hydrolysis process can be considered soaps.