On which side of neutrality `(pH-7)`, the isoelectric point of the following amino acids will lie ?
(a) `H-underset(underset(NH_(2))(|))(CH)-COOH`
(b) `underset(underset(CH_(2)-CH_(2)-COOH)(|))(H_(2)N-CH-COOH)`
( c) `underset(underset((CH_(2))_(4)-NH_(2))(|))(H_(2)N-CH-COOH)`.

Answer

To determine on which side of neutrality (pH 7) the isoelectric point of the given amino acids lies, we will analyze each amino acid based on the number of acidic (COOH) and basic (NH2) groups it possesses. The isoelectric point (pI) is the pH at which the amino acid has no net charge.

### Step-by-Step Solution:

1. **Identify the Structure of Each Amino Acid**:
- (a) `H₂N-CH(COOH)-COOH`: This amino acid has one NH2 group and two COOH groups.
- (b) `H₂N-CH₂-CH(COOH)-COOH`: This amino acid has one NH2 group and two COOH groups.
- (c) `H₂N-CH₂-CH₂-CH₂-CH(COOH)-NH₂`: This amino acid has two NH2 groups and one COOH group.

2. **Classify Each Amino Acid**:
- **Amino Acid (a)**:
- It has one NH2 and two COOH groups, indicating it is acidic.
- **Isoelectric Point**: Since it is acidic, its isoelectric point will be less than 7.
- **Amino Acid (b)**:
- Similar to (a), it has one NH2 and two COOH groups, making it acidic.
- **Isoelectric Point**: Again, it will be less than 7.
- **Amino Acid (c)**:
- This amino acid has two NH2 groups and one COOH group, indicating it is basic.
- **Isoelectric Point**: Since it is basic, its isoelectric point will be greater than 7.

3. **Conclusion**:
- For amino acid (a): Isoelectric point is less than 7 (acidic).
- For amino acid (b): Isoelectric point is less than 7 (acidic).
- For amino acid (c): Isoelectric point is greater than 7 (basic).

### Final Answer:
- Amino acids (a) and (b) have isoelectric points on the acidic side (less than 7).
- Amino acid (c) has an isoelectric point on the basic side (greater than 7).