What is geometrical isomerism and what type of compounds do exhibit it?

What is the origin of geometrical isomerism in alkenes ?

Explain Frenkel defect in ionic crystals. What type of compounds exhibit this defect ?

Define metamerism. What type of compounds do show it? Give an example.

Square planar complexes with a coordination number four exhibit geometrical isomerism whereas tetrahedral complexes do not, why?

Why do alkynes not show geometrical isomerism ?

(a) Square planar complexes with coordination number four exhibit geometrical isomerism whereas tetrahedral complexes do not , why ? (b) Three geometrical isomers of the square planar complex [Pt(NH_(3))(H_(2)O)(py)(NO_(2))]^(+) are possible . What are they ?

The alkene that exhibits geometrical isomerism is

The alkene that exhibits geometrical isomerism is

Species which will exhibit geometrical isomerism among the following is/are?

Assertion (A) Complexes of MX_(6) and MX_(5)L type (X and L are unidentate) do not show geometrical isomerism. Reason (R) Geometrical isomerism is not shown by complexes of coordination number 6.