Why are carbohydrates generally optically active?

Explanation

**Step-by-Step Solution:**

1. **Understanding Optical Activity**: Optical activity refers to the ability of a substance to rotate the plane of polarized light. This property is commonly observed in certain organic compounds, including carbohydrates.

2. **Chirality in Carbohydrates**: For a carbohydrate to be optically active, it must contain one or more chiral centers (chiral carbons). A chiral carbon is defined as a carbon atom that is bonded to four different substituents or groups. This unique arrangement allows for non-superimposable mirror images, which is a characteristic of chiral molecules.

3. **Identifying Chiral Carbons**: In carbohydrates, such as glucose, we can identify chiral carbons by examining their structure. For instance, in the case of glucose:
- The structure of glucose contains several carbon atoms, some of which are bonded to different groups (like hydroxyl groups, hydrogen atoms, and other carbon chains).
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