Question

Drop a crystal of copper sulphate or
potassium permanganate into a glass
of hot water and another containing
cold water. Do not stir the solution.
Allow the crystals to settle at the
bottom.
What do you observe just above the
solid crystal in the glass?
What happens as time passes?
What does this suggest about the
particles of solid and liquid?
Does the rate of mixing change with
temperature? Why and how?​

Answer 1

Explanation:

When the crystal of the salt ( copper sulphate or potassium permanganate) is added to hot water, it dissolves in it. Even without stirring, it can be observed after some time that the crystal will change the color of the water. If the crystal is of potassium permanganate, the water will turn purple, else if a crystal of copper sulphate is added, the water will turn blue. This is due to the breakdown of particles into smaller pieces and their movement into the intermolecular spaces of water.

The opposite happens in cold water. It does not breaks down.

This is because of the process of diffusion. It changes with temperature.