Question

3. Give reason for the following observations.
(a) Naphthalene balls disappear with time without leaving
any solid
(b) We can get the smell of perfume sitting several metres
away.
increasing order of forces​

Answer 1

Answer:

(a) Naphthalene balls undergo sublimation due to which it converts directly into vapours and disappear into air without leaving any solid.

(b) The particles of perfume diffuse rapidly into the air and its smell can be felt while sitting several metres away.

The force of attraction between the particles increases as we go from liquid to gas so the required order is: Oxygen<water<sugar.

I hope it helps you....

Answer 2

Answer:

(A) Naphthalene balls disappears leaving no solid because it undergoes the process of sublimination in which solid changes directly into gas

(B) The particles of gases moves randomly at high speed so we can smell the perfume sitting several meters away