Question

4. Fats in this experiment are hydrolyzed by saponification with base. Why do you hydrolyze with KOH and not with an acid like HCl?

5. In the Procedure section, you are cautioned to use petroleum ether and diethyl ether in the hood and not to have any flames in the laboratory. Why must you exercise these precautions?

Answer 1

1. Saponification means formation of soaps from fats. Fats contains triglycerides having ester linkages. When we add base, OH- reacts with ester forms soap and glycerine. If we add HCl then the solution becomes acidic then the reaction becomes very slow and some times there is no reaction. So we have to add base like KOH to maintain reaction conditions.
2. ​petroleum ether and diethyl ether are highly volatile and flammable , having very low flash points and forms explosive vapours.so these ethers easily catches the fire.

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