On heating glucose with Fehling solution. We get a precipitate whose colour is?

Options

A. Yellow
B. Red
C. Black
D. White

Answer

To determine the color of the precipitate formed when glucose is heated with Fehling's solution, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Fehling's Solution**:
Fehling's solution is a chemical reagent used to test for the presence of reducing sugars, such as glucose. It consists of two solutions: Fehling's A (copper(II) sulfate) and Fehling's B (alkaline tartrate).

2. **Reaction with Glucose**:
When glucose is heated with Fehling's solution, it acts as a reducing agent. The aldehyde group in glucose (CHO) is oxidized to a carboxylic acid (COOH).

3. **Formation of Copper(I) Oxide**:
During this reaction, the copper(II) ions (Cu²⁺) in Fehling's solution are reduced to copper(I) oxide (Cu₂O). This is a key step in the reaction.

4. **Precipitate Formation**:
The copper(I) oxide (Cu₂O) that forms is insoluble in water and precipitates out of the solution.

5. **Color of the Precipitate**:
The precipitate of copper(I) oxide is known to have a characteristic color. When formed, it typically appears red.

### Final Answer:
Thus, the color of the precipitate formed when glucose is heated with Fehling's solution is **red**.

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