Question

when water containing washing powder is stirred vigorously, the foam floats above water .why?

Answer 1

When water is mixed with washing powder, white mass of bubbles are formed called lather which separates out and floats above the water surface because it is less dense than the water.

Answer 2

Explanation:

When water containing washing powder is stirred vigorously then the particles of washing powder start to dissolve in water. As a result, there is formation of white foam which is called lather.

This foam or lather floats above water because it is light in weight as compared to water.

Thus, we can conclude that density of foam is less as compared to water that is why it floats above the surface of water.