Question

Most stable conformation of n-butane

• A. Anti form
• B. Gauche form
• C. Skew form
• D. Fully eclipsed form

Hint:

Greater distance between bulky groups means greater stability.

Answer 1

The Correct Option is A

Concept:
Conformational stability depends upon torsional strain and steric hindrance.
Step 1:
In anti conformation, two methyl groups remain opposite to each other. \[ 180^{\circ} \] apart.
Step 2:
Maximum separation minimizes steric repulsion.
Step 3:

• Gauche form has some steric strain
• Eclipsed form has maximum torsional strain
Step 4:
Thus most stable conformation is: \[ \boxed{\text{Anti form}} \] \[ \boxed{\text{Correct Option = (1)}} \]