Question

A large crystal of potassium permanganate is placed at bottom of a beaker of cold water ad left for several hours .
describe what would be seen 1. after 5 mins 2. after several hours
explain your answer using idea of particles
name two processes that takes place during the experiment

Answer 1

when we place the poatssium permenganate crystal at the bottom of a beaker of cold water and eft for several hours we observe that :

--->The purple colour of the KmNO4 crystals spreads into the water due to diffusion property of particles.

The property of diffusion gives us two conclusions about the nature of matter:
--> That matter is made up of tiny particles and
---> that the particles of matter are constantly moving

Answer 2

When a piece of Potassium permanganate (KMnO₄) is added to or placed at the bottom of a beaker which contains cold water, then the water turns into a purple coloured solution.

1. The colour of the solution is dark purple after 5 mins of the addition of the KMnO₄ piece to the water. This is due to diffusion of the KMnO₄ particles in the water.

2. After several hours, the colour of the solution may change to a purple shade that is lighter than the initial colour.

3. This is because the solution of water and KMnO₄ is made up of very tiny particles which get dispersed and spread amongst themselves. When the KMnO₄ particles are together, they give a dark purple colour. As they get dispersed in the water, the purple particles will spread making the solution lighter in colour.

4. The 2 processes that are taking place in this experiment are diffusion and dispersion.