Q
QuestionBiochemistry

What color changes occur during a positive result of the Benedict's test?
10 months agoReport content

Answer

Full Solution Locked

Sign in to view the complete step-by-step solution and unlock all study resources.

Step 1:
I'll solve this problem step by step, focusing on the Benedict's test color changes.

Step 2:
: Understanding the Benedict's Test

The Benedict's test is a chemical test used to detect the presence of reducing sugars, including simple sugars like glucose, fructose, and lactose. The test involves heating a sample with Benedict's reagent (a blue solution containing copper sulfate).

Step 3:
: Color Change Progression

During a positive Benedict's test, the color changes progressively through several stages: - Initial color: Blue (before heating) - First color change: Green (indicates a small amount of reducing sugar) - Next color change: Yellow (indicates a moderate amount of reducing sugar) - Final color change: Orange to Brick Red (indicates a high concentration of reducing sugar)

Step 4:
: Chemical Explanation

The color changes occur because the copper sulfate in Benedict's reagent is reduced by the sugar, causing a transformation in the copper ions' oxidation state. This reduction leads to the characteristic color progression.

Final Answer

In a positive Benedict's test, the color changes from blue → green → yellow → orange/brick red, with the final color indicating the concentration of reducing sugars present in the sample.