What is the criteria for optical activity . Give two examples of chiral molecules .

Explanation

Optical activity : The property of rotating the plane polarized light by a chemical substance is called optical activity .
`to` If the plane polarised light rotates in clock wise direction then it is dextro rotatory [(+) (or) d-forms].
`to` If the plane polarised light rotates in anti-clock wise direction condition then it is laevo rotatory [(-) or l-form] .
Crieteria for optical activity :
1) Chirality (or) dissymmetry is the necessary and sufficient condition for a molecule to show optical activity .
Chirality : The object which are non-superimposable on their mirror images are said to be chiral and this property is known as chirality .
2) Asymmetry (absence of symmetry) of the molecule is responsible for the optical activity of organic compounds .
Examples of chiral molecules :
i) 2-Butanol (ii) 2-Chlorobutane iii) 2-Bromopropanic acid .