How Chemistry Makes Candles Burn Brightly

Wax is fuel—usually paraffin or beeswax—that stores chemical energy until it burns.
The wick’s job is to draw melted wax upward by capillary action.
Heat from the flame vaporizes liquid wax, and it’s the vapor, not the solid, that actually burns.
Combustion of hydrocarbons in wax releases carbon dioxide, water, heat, and light.
The flame glows yellow because tiny soot particles get heated until they glow.
Blue at the base of the flame shows complete combustion where oxygen is plentiful.
Steady flame shape comes from the balance of heat rising and air flowing in.
Fragranced candles release volatile molecules along with combustion products, creating aroma.
Candle smoke is unburned carbon particles; relighting the smoke trail can ignite the wick.
Chemistry of light—candles emit both visible light and infrared, warming and brightening a room.