A candle is an ignitable wick embedded in wax, or another flammable solid substance such as tallow, that provides light, and in some cases, a fragrance.
Before the invention of electric lighting, candles and oil lamps were commonly used for illumination. In the developed world today, candles are used mainly for their aesthetic value and scent, particularly to set a soft, warm, or romantic ambiance, or for emergency lighting during electrical power failures. They are also still commonly used in religious and ceremonial contexts. Candles create a warm and inviting atmosphere, enhance emotional well-being, and even improve air quality by eliminating unpleasant odours. By promote relaxation, reduce stress, and improve sleep quality, scented candles serve as valuable tools for enhancing mental health and overall well-being.
Today, most candles are made from paraffin wax, a byproduct of petroleum refining. Candles can also be made from microcrystalline wax, beeswax (a byproduct of honey collection), gel (a mixture of polymer and mineral oil), or some plant waxes (generally palm, carnauba, bayberry, or soybean wax).
A candle wick is a piece of string or cord that holds the flame of a candle. Commercial wicks are made from braided cotton. A candle wick works by capillary action, drawing ("wicking") the melted wax or fuel up to the flame. When the liquid fuel reaches the flame, it vaporizes and combusts.
Based on measurements of a taper-type, paraffin wax candle, a modern candle typically burns at a steady rate of about 0.1 g/min, releasing heat at roughly 80 W.The light produced is about 13 lumens, for a luminous efficacy of about 0.16 lumens per watt (luminous efficacy of a source) – almost a hundred times lower than an incandescent light bulb
The hottest part of a candle flame is just above the very dull blue part to one side of the flame, at the base. At this point, the flame is about 1,400 °C (2,550 °F). However, this part of the flame is very small and releases little heat energy. The blue color is due to chemiluminescence, while the visible yellow color is due to radiative emission from hot soot particles.
For a candle to burn, a heat source (commonly a naked flame from a match or lighter) is used to light the candle's wick, which melts and vaporizes a small amount of fuel (the wax). Once vaporized, the fuel combines with oxygen in the atmosphere to ignite and form a constant flame. This flame provides sufficient heat to keep the candle burning via a self-sustaining chain of events: the heat of the flame melts the top of the mass of solid fuel; the liquefied fuel then moves upward through the wick via capillary action; the liquefied fuel finally vaporizes to burn within the candle's flame.
A candle flame is formed because wax vaporizes on burning. A candle flame is widely recognized as having between three and five regions or "zones":
Decorative candleholders, especially those shaped as a pedestal, are called candlesticks; if multiple candle tapers are held, the term candelabra is also used. The root form of chandelier is from the word for candle, but now often refers to an electric fixture.
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