Question

A gas jar containing air is placed upside down on a gas jar containing bromine vapours . It is observed after sometime , the gas jar containing air also becomes completely reddish brown.
(a) Explain why this happens .
(b) Name the process involved .

Answer 1

A gas jar containing air is placed upside down on a gas jar containing bromine vapours . It is observed after sometime , the gas jar containing air also becomes completely reddish brown.

Reason:
1. We observe that, after some time, the red brown vapours of bromine  spread out into the upper gas jar containing air.
In this way the upper gas jar which contains air in it also turns red-brown.
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. 

Answer 2

Answer:

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.

Explanation: