Question

What is the observation when kmn o4 is added to water and sodium dioxide?

Answer 1

If a solid sample of Potassium permanganate is placed in water, the water molecules will interact with the Potassium cations and the permanganate anions held in the crystal to break the ionic bonds that hold the crystal together.

This is a process of dissolving the crystal into solution. You will not be able to see the Potassium ions, but the permanganate ions are purple even in solution and you will see the water slowly darken (perhaps turning pink or violet first near the solid and finally taking on a uniform purple color).

This second phase is the diffusion of the the ions into the solvent. This process will speed up if the solution is heated or stirred.

Eventually one ends up with a homogeneous solution of Potassium permanganate in water.