Question

what change occurs in the colour of iodine vapour in the lower gas jar

Answer 1

Explanation:

the colour will be violet or purple

hope it will help you

Answer 2

This mixing is due to Diffusion of Bromine vapour into air. Air from upper jar also diffuses into lower jar though we cannot see it. So, diffusion is the process in which mixing of substances with another substance takes place due to motion of particles.