The dihedral angle in staggered form of 1,1,1-Trichloro ethane is ________ degree. (Round off to the Nearest Integer).
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For any ethane-like molecule (X$_3$C-CY$_3$), the staggered conformation is the most stable, and the dihedral angle between adjacent substituents is always 60°. The eclipsed conformation is the least stable, with a dihedral angle of 0°.
The molecule is 1,1,1-trichloroethane, which has the chemical formula CH$_3$-CCl$_3$.
We are considering the rotation around the C-C single bond. To visualize the dihedral angle, we use a Newman projection.
Let's place the CH$_3$ group in the front and the CCl$_3$ group in the back.
- The front carbon has three hydrogen atoms attached.
- The back carbon has three chlorine atoms attached.
There are two main conformations: eclipsed and staggered.
- In the eclipsed conformation, the substituents on the back carbon are directly behind the substituents on the front carbon. The dihedral angle between a front C-H bond and a back C-Cl bond is 0$^\circ$.
- In the staggered conformation, the substituents on the back carbon are positioned exactly in the middle of the substituents on the front carbon to minimize steric repulsion. This is the most stable conformation.
In this staggered arrangement, the angle between any C-H bond on the front carbon and the nearest C-Cl bond on the back carbon is 60$^\circ$. This is the dihedral angle.
Therefore, the dihedral angle in the staggered form of 1,1,1-trichloroethane is 60 degrees.
