a. At low temperatures, 1,1,2, trichloro ethane is not free to rotate about the carbon-carbon bond. It will be stuck in its lowest energy position. Is 1,1,2, trichloro
ethane a chiral molecule when trapped in this position?
1,1,2, trichloro ethane is chiral all of the time
1,1,2, trichloro ethane is chiral only when bond rotation is restricted
1,1,2, trichloro ethane is not chiral when bond rotation is restricted
1,1,2, trichloro ethane is never chiral
never chiral
bonjo's answer is wrong
I have to agree with bonjo.
This question is tricky because if a molecule is chiral, it is irrelevant whether it can rotate around the axis or not, like as presented in this case.
HOWEVER, this molecule is not chiral to begin with, so it is never chiral.
It's not chiral because neither carbon has four DIFFERENT groups (a prerequisite of chirality in tetrahedral configurations)
wikipedia dot org/wiki/1,1,2-Trichloroethane
also from wikipedia: "For tetrahedral molecules, the molecule is chiral if all four substituents are different."
ONLY when bond is restricted
To determine if 1,1,2-trichloroethane is a chiral molecule when bond rotation is restricted, we first need to understand the concept of chirality. A molecule is considered chiral if it cannot be superimposed on its mirror image.
In the case of 1,1,2-trichloroethane, it consists of a carbon atom bonded to three chloro atoms and another carbon atom. When the molecule is free to rotate about the carbon-carbon bond, the chlorine atoms can position themselves in different spatial arrangements. This creates different stereoisomers, some of which are mirror images of each other and thus chiral.
However, when the molecule is trapped in its lowest energy position at low temperatures, bond rotation is restricted, and the molecule becomes fixed in a specific spatial arrangement.
In this case, 1,1,2-trichloroethane is not free to undergo any change in its spatial arrangement, meaning it remains in a single conformation. Therefore, when bond rotation is restricted, 1,1,2-trichloroethane is not chiral.
So, the correct answer is "1,1,2-trichloroethane is not chiral when bond rotation is restricted."