Concept:Matter is made up of tiny particles with empty spaces between them, and this can be shown when one substance spreads into another without any external force.
Explanation:When potassium permanganate (
KMnO4​) is added to water, its purple colour spreads evenly throughout the water on its own.
This happens because the
KMnO4​ particles move into the empty spaces present between the water molecules.
This process is called diffusion, where particles move from a region of higher concentration to a region of lower concentration.
Diffusion can take place only when the particles of the medium have sufficient space between them.
Therefore, the even distribution of
KMnO4​ in water directly proves that particles of matter have enough space between them.
The other options do not clearly show this fact.
Boiling of water shows a change of state from liquid to gas.
Breaking an iron nail is only a physical change and does not show interparticle spaces.
Lighting an incense stick shows movement of particles, but the uniform mixing of
KMnO4​ in water is the best example of space between particles.
Answer:Potassium permanganate got evenly distributed in water (Option B).