Question

30.A drop of liquid bromine is place in the bottom of a gas jar. Brown fumes of bromine vapour slowly spread through the whole gas jar. Why does this happen?

Answer 1

This is because diffusion has taken place in the gas jar since gases show the property of moving continuously in the air that's why Brown fumes of bromine vapour spread through the whole glass jar

Answer 2

Diffusion is the name of this phenomena, it happens in liquids and solids ( Atomic diffusion ) as well although in solids it is a very slow process.In liquids it is quicker, imagine putting a drop of dye into a bowl of clear water, after a while all the water will be colored.