Question

A scientist performed a hydrolysis reaction on trimyristin to obtain myristic acid. The student wants to confirm if the reaction worked. During the melting point measurement, a 50:50 (by weight) mixture of the starting trimyristin and the product myristic acid was found to be similar to that of trimyristin alone. According to the mixed melting point concept, this result may indicate that:

a) trimyristin was hydrolyzed to myristic acid

b) trimyristin was not hydrolyzed to myristic acid

c) trimyristin is the same as myristic acid

d) trimyristin was decomposed during the hydrolysis reaction

e) none of the above

Answer 1

A scientist performed a hydrolysis reaction on trimyristin to obtain myristic acid. The student wants to confirm if the reaction worked.

During the melting point measurement, a 50:50 (by weight) mixture of the starting trimyristin and the product myristic acid was found to be similar to that of trimyristin alone. According to the mixed melting point concept, this result may indicate that:

trimyristin was not hydrolyzed to myristic acid (Option B) because in the above observation melting of the 50:50 (by weight) ratio mixture is equal to the melting point of trimyristin whose value is 56-58 C whereas melting point depression should be around 42-50 C.

Though trimyristin and myristic acid both the compounds have same melting point range they are referred as impure substances and depression of melting point should be observed.

As the mixture did not show melting point depression this infer that the two compounds were same and no impure substances are present.

This says that the trimyristin did not hydrolysed to myristic acid and remained as same.