Candle is a daily lighting tool, mainly made of paraffin. In ancient times, it was usually made of animal fat. Can burn and emit light. In addition, candles have a wide range of uses: they are also important for birthday banquets, religious festivals, collective mourning, ceremonies and ceremonies. In literary and artistic works, candles have the symbolic meaning of sacrifice and dedication.

The main raw material of candles is paraffin wax (C₂₅H₅₂), which is prepared from waxy fractions of petroleum by cold pressing or solvent dewaxing. It is a mixture of several higher alkanes, mainly n-docosane (C22H46) and n-bis Octadecane (C28H58) contains about 85% carbon and 14% hydrogen. The added auxiliary materials include white oil, stearic acid, polyethylene, flavors, etc. Among them, stearic acid (C17H35COOH) is mainly used to improve the softness, and the specific addition depends on the type of candle produced.

The candle burning we see is not the burning of paraffin solids, but the ignition device ignites the cotton wick, and the heat released makes the paraffin solids melt and revaporize to generate paraffin vapor, which is combustible. When the candle is ignited, the initial flame burns is smaller and gradually becomes larger, and the flame is divided into three layers (outer flame, inner flame, and flame core). The flame core is mainly candle vapor, the temperature is the lowest; the inner flame paraffin wax is not fully burned, and the temperature is higher than the flame core, and contains carbon particles; the outer flame is in full contact with the air, the flame is the brightest, the combustion is full, and the temperature is the highest. Therefore, when a matchstick is quickly put into the flame and taken out after about 1 second, the part of the matchstick that contacts the outer flame will first turn black.

At the moment when the candle is blown out, a wisp of white smoke can be seen. Use a burning match to light the wisp of white smoke, which can reignite the candle, so it can be proved that the white smoke is a solid produced by the condensation of paraffin vapor. Tiny particles.

When a candle burns, the products of combustion are carbon dioxide and water. Chemical expression: C25H52+O2→(ignite) CO2+H2O. The burning phenomenon in the oxygen cylinder is that the flame emits bright white light, emits heat, and water mist appears on the bottle wall.

Simple proof experiment:

Light the candle, cover a cold and dry beaker on the candle for 5 minutes, and then quickly turn the beaker over. It is found that the inner wall of the beaker becomes blurred and water droplets are formed, indicating that the candle burns and produces water.

Add a small amount of clarified lime water to the beaker and shake, and observe that the clarified lime water becomes turbid, indicating that the candle burns to generate carbon dioxide.

There are many types of candles produced. According to the purpose of use, they can generally be divided into two categories: daily lighting candles (normal candles) and handicraft candles (special purpose candles). Lighting candles are relatively simple, usually white rod-shaped candles. Craft candles can be subdivided into many types. First, they can be divided into jelly craft candles and incense craft candles. Generally, it shows various colors due to the addition of ingredients (such as birthday candles), and the shape needs to be made into various forms (such as spiral, digital, etc.), which can integrate novelty, decoration, ornamental, and functionality.

The flame of the candle is divided into three parts, divided into outer flame, inner flame and flame core. The outer flame has the highest temperature, the flame core has the lowest temperature, and the inner flame has the brightest brightness.

In addition, candles can also be divided into two types: rough wax and smooth wax. Generally, the surface of rough wax often has a smell, and there is a layer of hoarfrost on it. Different rough waxes will bring different smells, such as in the bedroom. Put some lavender-flavored candles to play a hypnotic and calming effect. You can put ocean-scented candles in the bathroom, and you can also put some loose candles to repel mosquitoes in summer; while the smooth wax has no smell, and the surface of the wax body is very smooth. , Easy to make a beautiful shape.

According to the shape, candles can be generally divided into extruded cylindrical wax, pointed bamboo wax, torch wax, floating wax, round wax, flat wax, etc. There are also many colors. These candles are more delicate in use, such as pointed bamboo wax. They are suitable for being placed on candlesticks during meals and placed in the middle of the dining table. They are especially commonly used in Western food. If the home decoration is European style, it can also be placed in the living room. Decorations. Bleaching wax is commonly found in bars. Pour water in a container and place the wax on the water. It will float on the water. It has a special mood under the dark candlelight. Bleaching wax is often used in young people’s homes, especially in couples’ rooms. Not only can you use sharp bamboo wax for candlelight dinners, but also bleaching wax will bring good results.