(1) In candle, wax molecules turninto a gaseous state and burn atthe top. The molecules which areon the outside get plenty of oxygenand burn completely givingmaximum heat. Inside this zone,particles don’t get full supply ofoxygen and burning is incompleteleaving carbon particles (as smoke).This zone gives moderate heat. Theunburnt particles come down in thedark zone (zone of no combustion).At the bottom, some unburntparticles get oxygen and burn with ablue flame.