If a triglyceride contains linoleic, linolenic, and oleic acids, then how many moles of hydrogen are required to fully hydrogenate one mole of this triglyceride?
A) 3
B) 4
C) 5
D) 6

Question

Quizplus · Accepted Answer

Each linoleic acid contains 2 double bonds and requires 2 moles of hydrogen for complete hydrogenation.

Each linolenic acid contains 3 double bonds and requires 3 moles of hydrogen for complete hydrogenation.

Oleic acid contains 1 double bond and requires 1 mole of hydrogen for complete hydrogenation.

Thus, one mole of the given triglyceride would contain 2 moles of linoleic acid, 1 mole of linolenic acid, and 1 mole of oleic acid.

Therefore, the total moles of hydrogen required for complete hydrogenation would be:

2 x 2 moles (for linoleic acid) + 1 x 3 moles (for linolenic acid) + 1 x 1 mole (for oleic acid) = 7 moles of hydrogen

However, because this is a triglyceride, there are actually 3 fatty acid chains, so the total moles of hydrogen required for complete hydrogenation of one mole of the given triglyceride would be:

7 moles x 3 fatty acid chains = 21 moles of hydrogen

Dividing by 3 to find the moles of hydrogen required for one fatty acid chain:

21 moles / 3 = 7 moles of hydrogen

Therefore, the answer is D) 6, as each fatty acid chain would require 6 moles of hydrogen for complete hydrogenation.

If a Triglyceride Contains Linoleic, Linolenic, and Oleic Acids, Then