Question

Naphthalene ball disappear with time without leaving any solid

Answer 1

This is due to Sublimation .

Sublimation is the process by which solid changes directly into gaseous form .

Some substances like naphthalene, dry ice , camphor, arsenic etc. undergoes sublimation, i.e. they get directly change into gaseous state from solid state without changing into liquid form.

So the chemical phenomenon here is - "Sublimation".

Answer 2

Heya !

Here is your answer :-

The naphthalene balls disappear without leaving any solid because they undergo the sublimation reaction.

It is the type of reaction in which the solid changes its States to vapour without going through the state of liquid.