The least energetic conformation of cyclohexane is:

Options

A. Boat form
B. Half chair form
C. Chair form
D. Twisted boat form

Explanation

To determine the least energetic conformation of cyclohexane, we need to analyze the different conformations available for cyclohexane and their relative stabilities. Here’s a step-by-step solution:

### Step 1: Identify the conformations of cyclohexane
Cyclohexane can adopt several conformations, primarily:
- Chair form
- Boat form
- Half-chair form
- Twisted boat form

### Step 2: Analyze the stability of each conformation
1. **Chair Form**: This is the most stable conformation due to minimized steric strain and torsional strain. All hydrogen atoms are in staggered positions, which reduces repulsion.

2. **Boat Form**: This conformation is less stable than the chair form because it has steric strain between the hydrogen atoms at the "bow" and "stern" of the boat.

3. **Twisted Boat Form**: This conformation is slightly more stable than the boat form due to reduced steric interactions, but it is still less stable than the chair form.

4. **Half-Chair Form**: This is the least stable conformation because it has significant steric strain and torsional strain.

### Step 3: Determine the least energetic conformation
Since the least energetic conformation corresponds to the most stable conformation, we find that the chair form is the most stable, while the half-chair form is the least stable.

### Conclusion
The least energetic conformation of cyclohexane is the **Chair Form**.

### Final Answer
The answer is **Chair Form**.

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