Question

Which of the following compounds are chiral?
A. $Cis - 1,2 - Dichlorocyclohexane$
B. $trans - 1,2 - dichlorohexane$
C. $cis - 1,3 - Dichlorohexane$
D. $Trans - 1,3 - Dichlorohexane$

Answer 1

The concept of chirality is based on the concepts of spatial arrangement of the atoms which are attached to the central atom of the compound under consideration.
Chirality refers to the mirror-images which are also non-superimposable compounds. Asymmetric molecules or carbon have a chiral configuration.

Complete step by step answer:
In order to answer this question we need to know the definition of chiral carbon or molecule. Chirality refers to the compound which is non-superimposable with the mirror image of the same compound. A stereocenter refers to one of the carbon which is asymmetric in nature. Now, we will draw the structure of each of the compounds whose name is provided in the question and we would figure out if it is chiral or not.

Above shown is the figure of the compound which is provided to us in option A, the name of this compound is $Cis - 1,2 - Dichlorocyclohexane$ and it is an achiral compound as it does now have a non-superimposable mirror image.

Above shown is the figure of the compound which is provided to us in option B, the name of this compound is $trans - 1,2 - dichlorohexane$ and it is a chiral compound as it has a non-superimposable mirror image.

Above shown is the figure of the compound which is provided to us in option C, the name of this compound is $cis - 1,3 - Dichlorohexane$ and it is an achiral compound as it does not have a non-superimposable mirror image.

Above shown is the figure of the compound which is provided to us in option D, the name of this compound is $Trans - 1,3 - Dichlorohexane$ and it is a chiral compound as it has a non-superimposable mirror image.
So, the correct answer is Option D.

Note: For the purpose of determining the chirality of any compound the first step is to draw the structures of the compounds whose names are provided in the question.
Now, the carbons having four different groups attached to it could be considered a chiral carbon.