Why does candle give flame when it is burnt but why does coal burn without emitting a flame?

Why does candle give flame when it is burnt but why does coal burn wit

1.	Why does candle give flame when it is burnt but why does coal burn without emitting a flame?
Answer» A candle is made of wax in which a thick thread is inserted. When it is lighted melts by a match stick. A little of the wax forms gas. This gas combines with oxygen in the air to form flame. But coal is a natural fuel contains more carbon. When it is burnt it sends out carbon monoxide and carbon dioxide gases and becomes ember and does not emit a flame. Coal is the changed material of wood. Hence it does not emit a flame as it possesses a huge calorific value (heat).