Number of Staggered Ethane Conformations

Margie781

Ethane is a simple hydrocarbon molecule composed of two carbon atoms and six hydrogen atoms. It is possible for the molecule to adopt different conformations, or shapes, due to the flexibility of the bonds between the atoms. This discussion will focus on the number of staggered conformations ethane can adopt.The answer to this question is that ethane can adopt two staggered conformations. The two conformations are known as the "gauche" and "anti" conformations. The gauche conformation is slightly more stable than the anti conformation due to the fact that the hydrogens are slightly closer together in the gauche conformation. This allows for more efficient hydrogen bonding, which makes it more stable.

orangefrog252

Ethane is a C2H6 molecule with three carbon-carbon bonds. It has three main conformations, traditionally referred to as eclipsed, anti-periplanar, and staggered.

In the eclipsed conformation, both of the methyl groups are in line with the C=C bond, with the C-H bonds sustaining the overlap. This conformation is unstable and will quickly convert into one of the other two conformations

In the anti-periplanar conformation, the two methyl groups adjust the angle slightly to decrease the C-H bond overlap. This conformation is less stable than the alternative staggered conformation, which is the most common and stable conformation of ethane.

The staggered conformation involves the two methyl groups being at a 60-degree angle from one another, as well as from the C-C bond. This is the most favourable due to it being the conformation that involves the least amount of bond angle strain.

In total, ethane has two staggered conformations, with the other two configurations (anti-periplanar and eclipsed) being much less favourable.

Bluetoal

Ethane, an alkane with the chemical formula C2H6, has a total of seven different staggered conformations or "conformers". In chemistry, a conformer is a molecular structure that is in dynamic equilibrium with other molecular structures of the same compound.

The seven staggered conformations of ethane differ by the rotation of the two carbon atoms about the C-C single bond. The seven conformers are classified as eclipsed, gauche, gauche-like, anti, dihedral, dihedral-like and anti-like.

The most common staggered conformation of ethane is the anti conformation, where the two methyl (CH3) groups are arranged at an angle of 180° or "oppositional". In this form, there is no overlap between the electron clouds of the two carbon atoms and, therefore, maximum bond stability is achieved.

The other six staggered conformations of ethane are, in order of descending energy: the eclipsed conformation, the dihedral-like conformation, the dihedral conformation, the gauche-like conformation, and the gauche conformation. The eclipsed conformation is the least stable conformation, since the electron clouds of the two carbon atoms overlap.

To summarise, ethane has seven different staggered conformations, all classified by the rotation of the two carbon atoms relative to each other. The anti conformation is the most stable and the eclipsed conformation is the least stable.

For more information, you can check out this site which gives an in-depth look at the different conformations of ethane and how they are related: https://chem.libretexts.org/Ancillary_Materials/Organic_Chemistry/Organic_Chemistry_with_a_Biological_Emphasis/Structure_and_Stereochemistry_of_Organic_Molecules/Structure_and_Conformation_of_Alkanes/Conformation_of_Ethane