A smoke bomb is a

firework Fireworks are a class of low explosive pyrotechnic devices used for aesthetic and entertainment purposes. They are most commonly used in fireworks displays (also called a fireworks show or pyrotechnics), combining a large number of devices in ...

designed to produce a large amount of

smoke Smoke is a suspension of airborne particulates and gases emitted when a material undergoes combustion or pyrolysis, together with the quantity of air that is entrained or otherwise mixed into the mass. It is commonly an unwanted by-produc ...

upon ignition.

History

Early Japanese history saw the use of a rudimentary form of the smoke bomb. Explosives were common in Japan during the

Mongol invasions The Mongol invasions and conquests took place during the 13th and 14th centuries, creating history's largest contiguous empire: the Mongol Empire ( 1206-1368), which by 1300 covered large parts of Eurasia. Historians regard the Mongol devastatio ...

of the 13th century. Soft cased hand-held bombs were later designed to release smoke, poison gas, and

shrapnel Shrapnel may refer to: Military * Shrapnel shell, explosive artillery munitions, generally for anti-personnel use * Shrapnel (fragment), a hard loose material Popular culture * ''Shrapnel'' (Radical Comics) * ''Shrapnel'', a game by Adam C ...

made from

iron Iron () is a chemical element with Symbol (chemistry), symbol Fe (from la, Wikt:ferrum, ferrum) and atomic number 26. It is a metal that belongs to the first transition series and group 8 element, group 8 of the periodic table. It is, Abundanc ...

and

pottery Pottery is the process and the products of forming vessels and other objects with clay and other ceramic materials, which are fired at high temperatures to give them a hard and durable form. Major types include earthenware, stoneware and ...

. The modern smoke bomb was created in 1848, by the British inventor Robert Yale. He developed 17th-century Chinese-style fireworks and later modified the formula to produce more smoke for a longer period of time. Rauchbombe

Colored smoke Colored smoke is a kind of smoke created by an aerosol of small particles of a suitable pigment or dye. Colored smoke can be used for smoke signals, often in a military context. It can be produced by smoke grenades, or by various other pyrote ...

devices use a formula that consists of an

oxidizer An oxidizing agent (also known as an oxidant, oxidizer, electron recipient, or electron acceptor) is a substance in a redox chemical reaction that gains or " accepts"/"receives" an electron from a (called the , , or ). In other words, an oxid ...

(typically

potassium nitrate Potassium nitrate is a chemical compound with the chemical formula . This alkali metal nitrate salt is also known as Indian saltpetre (large deposits of which were historically mined in India). It is an ionic salt of potassium ions K+ and nitr ...

, KNO₃), a fuel (generally sugar), a moderator (such as sodium bicarbonate) to keep the reaction from getting too hot, and a powdered

organic dye A dye is a colored substance that chemically bonds to the substrate to which it is being applied. This distinguishes dyes from pigments which do not chemically bind to the material they color. Dye is generally applied in an aqueous solution and ...

. The burning of this mixture

boils A boil, also called a furuncle, is a deep folliculitis, which is an infection of the hair follicle. It is most commonly caused by infection by the bacterium '' Staphylococcus aureus'', resulting in a painful swollen area on the skin caused by ...

the dye and forces it out of the device, where it condenses in the atmosphere to form a smoke of finely dispersed particles. Home-made smoke bombs, even preceding Yale's 1848 invention, were and are most commonly used in pranks and street conflicts. They are typically made from materials that burn poorly and contained in vessels with a limited air intake that inhibit

combustion Combustion, or burning, is a high-temperature exothermic redox chemical reaction between a fuel (the reductant) and an oxidant, usually atmospheric oxygen, that produces oxidized, often gaseous products, in a mixture termed as smoke. Combus ...

. Because both the ingredients and uses are unpredictable, home-made smoke bombs are often categorized as an incendiary device.

References

{{commonscat, Smoke bombs Fireworks Pyrotechnics Smoke