Carbohydrates contain?

Options

A. `-OH` group
B. `-CHO` group
C. `gt C = O` group
D. All

Answer

**Step-by-Step Solution:**

1. **Understanding Carbohydrates**: Carbohydrates are organic compounds that primarily consist of three elements: carbon (C), hydrogen (H), and oxygen (O).

2. **General Formula**: The general formula for carbohydrates is represented as \( C_xH_{2y}O_y \). This formula indicates the ratio of these elements in carbohydrates.

3. **Modern Definition**: According to modern definitions, carbohydrates are classified as optically active polyhydroxy aldehydes or polyhydroxy ketones. This means they contain multiple hydroxyl (-OH) groups and either an aldehyde group (-CHO) or a ketone group (C=O).

4. **Examples of Carbohydrates**:
- **Glucose**: An example of a carbohydrate that contains an aldehyde group. Its structure includes multiple hydroxyl groups and one aldehyde group.
- **Fructose**: Another carbohydrate example, which contains a ketone group. It also has multiple hydroxyl groups.

5. **Functional Groups Present in Carbohydrates**: From the examples, we can conclude that carbohydrates contain:
- Hydroxyl groups (-OH)
- Aldehyde groups (-CHO) in aldoses (like glucose)
- Ketone groups (C=O) in ketoses (like fructose)

6. **Conclusion**: Therefore, carbohydrates contain hydroxyl groups, aldehyde groups, and ketone groups.

**Final Answer**: Carbohydrates contain hydroxyl groups (-OH), aldehyde groups (-CHO), and ketone groups (C=O).

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