Which of the following is the correct order of stability of conformations for `NH_(2)-CH_(2)-CH_(2)-OH`

Options

A. gauche `gt` eclipsed `gt` anti
B. gauche `gt` anti `gt` eclipsed
C. eclipsed `gt` gauche `gt` anti
D. anti `gt` eclipsed `gt` gauche

Explanation

To determine the correct order of stability of conformations for the molecule NH₂-CH₂-CH₂-OH, we need to analyze the different conformations: anti, gauche, and eclipsed.

### Step-by-Step Solution:

1. **Identify the Conformations**:
- The three main types of conformations are:
- **Anti**: The substituents are positioned opposite to each other, minimizing steric hindrance.
- **Gauche**: The substituents are positioned next to each other, leading to some steric strain but allowing for potential hydrogen bonding.
- **Eclipsed**: The substituents are aligned with each other, leading to maximum steric hindrance and torsional strain.

2. **Draw the Conformations**:
- **Anti Conformation**: In this conformation, the NH₂ and OH groups are positioned 180 degrees apart, which minimizes steric interactions.
- **Gauche Conformation**: In this conformation, the NH₂ and OH groups are positioned 60 degrees apart. This allows for some interaction between the groups, such as hydrogen bonding, but also introduces some steric strain.
- **Eclipsed Conformation**: In this conformation, the NH₂ and OH groups are aligned with each other (0 degrees apart), leading to maximum steric hindrance and torsional strain.

3. **Evaluate Stability**:
- The **Eclipsed** conformation is the least stable due to high steric hindrance and torsional strain.
- The **Gauche** conformation is more stable than eclipsed because of the possibility of hydrogen bonding, but less stable than anti due to some steric strain.
- The **Anti** conformation is the most stable as it minimizes steric hindrance and allows for optimal spatial arrangement of the groups.

4. **Order of Stability**:
- Based on the analysis, the correct order of stability for the conformations of NH₂-CH₂-CH₂-OH is:
- Anti > Gauche > Eclipsed

### Final Answer:
The correct order of stability of conformations for NH₂-CH₂-CH₂-OH is:
**Anti > Gauche > Eclipsed**