Geometrical isomerism:
The isomerism which arises due to frozen rotation about to bond in a molecule is known as geometrical or cis-trans isomerism. Conditions for geometrical isomerism: A compound will show geometrical isomerism if it fulfils the following two conditions:
1. There should be restricted (frozen) rotation about a bond in the molecule.
2. Both substituents on each carbon about which rotation is frozen (restricted) should be different.
Example:
