Question

For the determination of fatty acid composition, transesterification is done in a warm aqueous solution of

• A. KCl + methanol
• B. KOH + methanol
• C. NaOH + methanol
• D. H2O + methanol

Hint:

Transesterification is an important step in biodiesel production and fatty acid analysis, typically involving methanol and KOH as a catalyst.

Answer 1

The Correct Option is B

Step 1: Understanding transesterification.
Transesterification is the process where triglycerides (fats) are converted into methyl esters (fatty acid methyl esters, FAME) and glycerol by reacting with methanol. The process requires a catalyst, often KOH (potassium hydroxide), in methanol.
Step 2: Analyzing the options.
(1) KCl + methanol: This is incorrect as KCl is not a catalyst for transesterification.
(2) KOH + methanol: Correct — KOH acts as a strong base that catalyzes the transesterification reaction, converting fats into FAME.
(3) NaOH + methanol: This is another possible choice for transesterification but KOH is more commonly used.
(4) H2O + methanol: This is incorrect, as water is not used in transesterification and would hinder the reaction.
Step 3: Conclusion.
The correct answer is (2) KOH + methanol, as KOH is used as a catalyst for transesterification in fatty acid composition determination.