Question

A compound of the molecular formula is ${C_7}{H_{16}}$ show optical isomerism, the compound will be
(A) 2,3-dimethylpentane
(B) 2,2-dimethylbutane
(C) 2-methylhexane
(D) None of the above

Answer 1

Carbon element atomic number $6$ in its outermost shell four electrons are present so it has the capacity to make four bonds with other elements. Carbon makes bonds because after completion of octet the element becomes stable.

Complete step by step answer:
Chiral carbon plays a very important role in optical activity. If a compound does not have a chiral carbon then it means that compound is optically inactive. It means that the compound does not show optical activity.
Chiral carbon is carbon which completes its own valency by different four elements. That carbon is known as chiral carbon.
Optical isomers may be defined as the molecules having the same molecular formula but they form non-superimposable images of each other. The phenomenon is known as optical isomerism.
In 2,3-dimethylpentane one chiral carbon is present which makes four bonds with different atoms.
The molecular formula of 2,3-dimethylpentane is -
$C{H_3}CH2\mathop C\limits_{C{H_3}} H\mathop C\limits_{C{H_3}} HC{H_3}$
Hence option A is the correct option. The 2,3-dimethylpentane compound of the molecular formula is ${C_7}{H_{16}}$ shows optical isomerism.

Additional information: The non-super-impossible image is also known as enantiomer. And the optical isomer has the same properties like melting point, boiling point. This occurs because one enantiomer rotates the light at an angle then the other enantiomer rotates the same light with the same angle so the optical isomer has the same properties like melting point, boiling point.

Note:
Optical isomerism play an important role in biochemistry-
Most amino acids show optical activity. And many drugs are made by one optical isomer that improve pharmacological activities.
Optical isomers having physical and chemical properties are the same.