Why can't a candle burn by itself? It needs a wick to burn.

In fact, paraffin itself can be burned, but the ignition point is higher than the melting point (strictly speaking, paraffin is amorphous and has no melting point), so it can only be burned after providing a lot of heat to melt paraffin.

After adding the wick, it is easy to ignite just by melting a small amount of paraffin on the wick. Then the heat generated after combustion continuously melts the surrounding paraffin, so that the combustion can continue.

Before there was no electricity, paraffin wax was used for lighting. Paraffin is put in an aluminum lunch box, but the wick is drawn with cloth. Because the wick was too thick, the whole box of paraffin was finally ignited!

Wax does not burn when it exists alone. This is because in the combustion process, there is also a process of gasification of wax oil. If there is no gasification, liquid wax oil will put out the fire! In the burning process of candle or oil lamp, the fuel is sent from the oil tank up the wick to the burning part of the flame by capillary action, and when the fuel reaches the upper end, it begins to vaporize. Capillary force takes fuel to a flammable place and stores it there.