Question

camphor disappears without leaving any residue

Answer 1

camphor disappears without leaving any residue with the help of the process sublimation
In this the solid gets directly converted into gaseous state and vice versa without changing into liquid state! This happens because of the heat energy (kinetic energy) which enables it to do so!!
Hope this answer will help you☺️!!!

Answer 2

Camphor undergoes a process called sublimation in which a solid particle changes into vapour state without entering the liquid phase
thus camphor directly converts into vapour