Question

How many conformations are possible for ethane?

• A. 2
• B. 3
• C. Infinite
• D. One

Hint:

In molecules with single bonds, continuous rotation around the bond leads to an infinite number of conformations. Ethane is a classic example of such a molecule.

Answer 1

The Correct Option is C

Step 1: Defining Conformations
Conformations are distinct spatial arrangements of a molecule's atoms, achievable through rotation about single bonds.
Step 2: Examining Ethane
Ethane (C\(_2\)H\(_6\)) features two carbon atoms linked by a single bond, each also bonded to three hydrogen atoms.
Rotation about the C
C single bond results in varying spatial orientations of these hydrogen atoms.
Step 3: Quantifying Conformations
The rotation around the C
C bond is uninterrupted, yielding an endless spectrum of possible conformations as the dihedral angle between hydrogen atoms varies continuously.
Step 4: Aligning with Choices
Option (C) Infinite is correct, owing to the continuous rotation around the C
C bond, which allows for an unlimited number of conformations.Final Answer: Ethane possesses (C) Infinite possible conformations.