In the diacetyl method, diacetyl reacts with which to form a yellow product?

In the diacetyl method, diacetyl reacts with which to form a yellow product?

• A. Ammonia
• B. Urea
• C. Uric acid
• D. Nitrogen

Answer: (B)

In this colorimetric test, the diacetyl reagent reacts specifically with urea to form a yellow chromophore. The formation of that yellow product signals the presence of urea, and the intensity of the color correlates with how much urea is present, allowing quantification. Ammonia wouldn’t produce the same yellow chromophore under the same conditions, and uric acid or nitrogen don’t participate in this particular reaction to yield the yellow color, so they don’t serve as the readout in this assay.

In this colorimetric test, the diacetyl reagent reacts specifically with urea to form a yellow chromophore. The formation of that yellow product signals the presence of urea, and the intensity of the color correlates with how much urea is present, allowing quantification. Ammonia wouldn’t produce the same yellow chromophore under the same conditions, and uric acid or nitrogen don’t participate in this particular reaction to yield the yellow color, so they don’t serve as the readout in this assay.