Question

what are the changes that take place on burning an incence stick​

Answer 1

Answer:

If we light an incense stick (agarbatti) with a burning matchstick we find that after some time the whole incense stick burns away. During burning of incense stick, some pleasant smelling gases are produced (which go into the air) and ash is left behind. We cannot recombine the gases and the ash to get back the original incense stick. So, this is a change which cannot be reversed. Thus, the burning of an incense stick is an irreversible change.