Question

why does KCl turn violet on heating in the potassium vapour?

Answer 1

heya..
here is Ur answer.....
It is because of the Metal excess defect due to anionic vacancies.When KCl is heated with K(vap) the Cl- ions diffuse from the crysta to the surface in the K atoms form the K 9vap) are deposited.
hope this helps you ......