Explain the change of energy with a graph for the internal rotation of ethane about the $C-C$ bond after a $120^{\circ}$ rotation.
(N/A) The internal rotation of ethane about the $C-C$ bond leads to different conformational isomers.
$1$. The staggered conformation is the most stable form with minimum energy due to minimum torsional strain.
$2$. The eclipsed conformation is the least stable form with maximum energy due to maximum torsional strain.
$3$. $A$ rotation of $60^{\circ}$ from staggered to eclipsed increases the energy by $12.5 \ kJ \ mol^{-1}$.
$4$. $A$ further rotation of $60^{\circ}$ (total $120^{\circ}$) brings the molecule back to a staggered conformation,which is equivalent to the initial state in terms of energy.
Thus,after a $120^{\circ}$ rotation,the molecule returns to a staggered conformation,which is a minimum energy state.
$1$. The staggered conformation is the most stable form with minimum energy due to minimum torsional strain.
$2$. The eclipsed conformation is the least stable form with maximum energy due to maximum torsional strain.
$3$. $A$ rotation of $60^{\circ}$ from staggered to eclipsed increases the energy by $12.5 \ kJ \ mol^{-1}$.
$4$. $A$ further rotation of $60^{\circ}$ (total $120^{\circ}$) brings the molecule back to a staggered conformation,which is equivalent to the initial state in terms of energy.
Thus,after a $120^{\circ}$ rotation,the molecule returns to a staggered conformation,which is a minimum energy state.
Explore More
Similar Questions
The dihedral angle of the least stable conformer of ethane is $....\,^{\circ}$.
MediumNEET 2021
View SolutionWhich conformation of ethane has the lowest potential energy?
Medium
View SolutionGiven below are two statements:
Statement $I$: There are several conformers for $n$-butane. Out of those conformers, the fully eclipsed conformer (dihedral angle $0^{\circ}$) is the least stable and the anti-staggered conformer (dihedral angle $180^{\circ}$) is the most stable.
Statement $II$: As the dihedral angle increases from $0^{\circ}$ to $60^{\circ}$, torsional strain decreases from the fully eclipsed conformer $(X)$ to the gauche conformer $(Y)$.
In the light of the above statements, choose the correct answer from the options given below:
Statement $I$: There are several conformers for $n$-butane. Out of those conformers, the fully eclipsed conformer (dihedral angle $0^{\circ}$) is the least stable and the anti-staggered conformer (dihedral angle $180^{\circ}$) is the most stable.
Statement $II$: As the dihedral angle increases from $0^{\circ}$ to $60^{\circ}$, torsional strain decreases from the fully eclipsed conformer $(X)$ to the gauche conformer $(Y)$.
In the light of the above statements, choose the correct answer from the options given below:
DifficultJEE MAIN 2026
View SolutionThe most stable conformation for $n$-butane is
MediumKVPY 2010
View Solution$HO-CH_2-CH_2-CHO$
Which conformer of the above compound is most stable (consider the conformer across the $C_2-C_3$ bond)?
Which conformer of the above compound is most stable (consider the conformer across the $C_2-C_3$ bond)?
Medium
View SolutionVedclass Products
For Students
Vedclass Test Series
Mock tests in real JEE/NEET style with performance analysis. 5-day free trial.
Start Free TrialFor Teachers
Exam Paper Generator
Generate Set A/B/C/D exam papers from 7.5L+ questions in 2 minutes. 3 chapters free.
Try FreeFor Institutes
Online Exam Module
Live online exams with unlimited students, 360° analytics & white-label branding.
See Demo