which of the following does not reduce Benedict's solution ?

Options

A. Glucose
B. Fructose
C. sucrose
D. Aldehyde

Answer

To determine which of the following substances does not reduce Benedict's solution, we need to analyze each option based on their chemical properties and their ability to act as reducing agents.

### Step-by-Step Solution:

1. **Understanding Benedict's Solution**:
- Benedict's solution is a chemical reagent that contains copper(II) sulfate (CuSO4·5H2O), sodium citrate, and sodium carbonate. It is used to test for the presence of reducing sugars.

2. **Identifying Reducing Sugars**:
- Reducing sugars are carbohydrates that can donate electrons to reduce other molecules. Common examples include glucose and fructose, which both have free aldehyde or ketone groups.

3. **Analyzing Each Option**:
- **Option A: Glucose**:
- Glucose is a monosaccharide and a reducing sugar. It has an aldehyde group that can reduce Benedict's solution, changing its color from blue to green, yellow, or red depending on the concentration.
- **Option B: Fructose**:
- Fructose is also a monosaccharide and a reducing sugar. It can reduce Benedict's solution as well, resulting in a color change similar to glucose.
- **Option C: Sucrose**:
- Sucrose is a disaccharide composed of glucose and fructose linked by a glycosidic bond. It does not have a free aldehyde or ketone group, and therefore, it does not reduce Benedict's solution. Sucrose must be hydrolyzed into its constituent monosaccharides to exhibit reducing properties.
- **Option D: Aldehyde**:
- Aldehydes are known to be reducing agents. They can reduce Benedict's solution, resulting in a color change.

4. **Conclusion**:
- Based on the analysis, the substance that does not reduce Benedict's solution is **Option C: Sucrose**.

### Final Answer:
**Sucrose does not reduce Benedict's solution.**