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Colored fire is a common pyrotechnic effect used in stage productions, fireworks and by fire performers the world over. Generally, the color of a flame may be red, orange, blue, yellow, or white, and is dominated by blackbody radiation from soot and steam.
As early as the 15th century Leonardo da Vinci commented at length on the difficulty of assessing smoke, and distinguished between black smoke (carbonized particles) and white 'smoke' which is not a smoke at all but merely a suspension of harmless water particulates. [64] Smoke from heating appliances is commonly measured in one of the ...
Smoke with a suitable composition can be used as a fire suppression agent.A pyrotechnic composition similar to black powder, composed of 15% charcoal and 85% potassium nitrate, generates thick smoke composed of particles of mainly potassium carbonate, which has fire extinguishing properties.
Care should be taken to avoid formation of solid particles in the flame zone, whether metal oxides or carbon; incandescent solid particles emit black-body radiation that causes "washing out" of the colors. Addition of aluminium raises the flame temperature but also leads to formation of solid incandescent particles of aluminium oxide and molten ...
Strontium carbonate is used as a fire retardant in some gunpowders. Flame suppressants. Potassium nitrate and potassium sulfate are commonly used. Opacifiers. Some solid rocket propellants have problems with radiative heat transfer through the material, which may lead to explosion. Carbon black and graphite are often used to inhibit this effect.
The transitions are often apparent in fires, in which the color emitted closest to the fuel is white, with an orange section above it, and reddish flames the highest of all. [7] A blue-colored flame only emerges when the amount of soot decreases and the blue emissions from excited molecular radicals become dominant, though the blue can often be ...
Fire is the rapid oxidation of a material (the fuel) in the exothermic chemical process of combustion, releasing heat, light, and various reaction products. [1] [a] At a certain point in the combustion reaction, called the ignition point, flames are produced.
Another type of smoke grenade is filled with white phosphorus (WP), which is spread by explosive action. The phosphorus catches fire in the presence of air, and burns with a brilliant yellow flame, while producing copious amounts of white smoke (phosphorus pentoxide). WP grenades double as incendiary grenades.