Question

Dispersion cannot take place in a glass slab yes or no

Answer 1

$\bold {ANSWER :-}$ Yes, dispersion cannot take place in a glass slab.

$\bold {Reason :-}$ Because white light is made up of ALL visible wavelengths, its colors can be separated (dispersed) by this difference in behavior. When light passes through glass, it encounters TWO interfaces--one entering and the other leaving. ... A glass prism is able to produce a spectrum but a rectangular glass slab does not.

Answer 2

No of course it can take place from the corners.