Question 3 (a)
Give reason for the following observations.
a. Naphthalene balls disappear with time without leaving any solid.
a. Naphthalene undergoes sublimation easily i.e., the change of state of naphthalene from solid state to gaseous state without intervention of liquid state. Thus, naphthalene balls keeps on forming naphthalene vapours which disappear into the air with time without leaving any solid.