For a neutral amino acid (X), isoelectric point is 5.8. Now its solubility at this point in water is

Options

A. maximum
B. minimum
C. zero
D. unpredictable

Answer

To solve the question regarding the solubility of a neutral amino acid (X) at its isoelectric point (pI) of 5.8, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding the Isoelectric Point (pI)**:
- The isoelectric point (pI) is the pH at which an amino acid has no net charge. For neutral amino acids, this point is typically around 5.5 to 6.2.

2. **Identifying the Nature of the Amino Acid**:
- Since the given pI is 5.8, which falls within the range of 5.5 to 6.2, we can classify amino acid X as neutral.

3. **Solubility of Amino Acids at pI**:
- At the isoelectric point, amino acids tend to aggregate because they have no net charge. This aggregation leads to reduced solubility in water.

4. **Conclusion**:
- Therefore, for the neutral amino acid X at its isoelectric point of 5.8, the solubility in water is at its minimum.

5. **Final Answer**:
- The correct option regarding the solubility of amino acid X at its isoelectric point is **minimum**.