Friday, November 8, 2019
Gun Powder Essay Example
Gun Powder Essay Example Gun Powder Essay Gun Powder Essay Gunpowder (a. k. a black powder) is a mixture of sulphur, charcoal, and potassium nitrate. Gunpowder is a compound that can be made just using potassium nitrate and charcoal, but without the sulphur, the powder is not as strong as with the sulphur. It burns rapidly, producing a volume of hot gas that is made up of carbon dioxide, water, and nitrogen, and a solid residue of potassium sulfide. Because of its burning rate and properties and the amount of heat and gas volume that it can generate, gunpowder has and is been widely used as a propellant in firearms and as a pyrotechnic composition in fireworks. The term of gunpowder also refers broadly to any powder that has propellant. Though modern firearms do not use the traditional gunpowder, instead they use smokeless powder. The burn rate of gunpowder can be changed by corning. Corning first compresses the fine black powder formula into blocks with a fixed density of around 1. 7 g/cm?. The blocks are then broken up into granules. These granules are then sorted by size to give various grades of black powder. Different grades of black powder are use for different things. In the U. S. standard grades of black powder runs from the coarse Fg grade that are used in large bore rifles and small cannons. Through FFg which is used in medium and small-bore weapons such as muskets and fusils, FFFg used in small-bore rifles and pistols, and FFFFg that is used in extreme small bore, short pistols and for priming flintlocks. A simple, in a way, chemical equation for the combustion of black powder is 2 KNO3 + S + 3 C K2S + N2 + 3 CO2. The more accur ate, though simplified a bit, is 10 KNO3 + 3 S + 8 C 2 K2CO3 + 3 K2SO4 + 6 CO2 + 5 N2. : Burning gunpowder does not take place as a single reaction, and the byproducts are not easily predicted. One studys results showed that it produced: 55. 91% solid products: potassium carbonate, potassium sulfate, potassium sulfide, sulfur, potassium nitrate, potassium thiocyanate, carbon, ammonium carbonate. 42. 98% gaseous products: carbon dioxide, nitrogen, carbon monoxide, hydrogen sulfide, hydrogen, methane, and 1. 11% water. Black powder that is made with sodium nitrate tends to be hygroscopic, unlike black powders made from saltpeter. Because black powder that is made with saltpeter is less affected by moisture in the air, and it can be stored unsealed for centuries without degradation if it is kept dry. Contrasting, black powder made with sodium nitrate has to be sealed from the moisture in the air to remain stable for long periods. Advantages In firearms, black powder allows loading by volumetric measure, where as smokeless powder requires precise measuring of the charge by weight to prevent damage due to overloading, but damage by overloading is still possible with black powder. In quarrying, high explosives are generally preferred for shattering rock. Though, because of its low brisance, black powder causes fewer fractures and results in more usable stone compared to other explosives, making black powder useful for blasting monumental rocks such as granite and marble. Black powder is well suited for blank rounds, or signal flares, burst charges, and rescue-line launches. Black powder is also used in fireworks for lifting the shells in rockets as fuel, and in certain special effects. Disadvantages Black powder has a low energy density compared to modern smokeless powders, and it produces a thick smoke that can impair aiming and reveal a shooters position. Combustion converts less than half the mass of black powder to gas. The rest of it ends up as a thick layer of soot inside the barrel. In addition the residue from burnt black powder is hygroscopic and a caustic substance. When moisture from the air is absorbed, the potassium oxide or sodium oxide turns into hydroxide, which will corrode used iron or steel gun barrels. Black powder arms must be well cleaned both inside and outside to remove the residue. The Matchlock musket, which is an early gun, would be unusable in wet weather because of powder in the pan being exposed and dampened, in which case soldiers would have to use the ends as clubs or use their bayonets. Other uses Besides its habitual use as an explosive, gunpowder has been occasionally employed for other purposes. After the Battle of Aspern-Essling (1809), the surgeon of the Napoleonic Army Larrey combated the lack of food for the wounded under his care by preparing a bouillon of horse meat seasoned with gunpowder because of the lack of salt. It was also used for sterilizing on ships when there was no alcohol. Christiaan Huygens experimented with gunpowder in 1673 in an early attempt to build an internal combustion engine, but he did not succeed in making a practical engine. Fireworks and Firecrackers also use gunpowder but use different brands and different chemicals. Black powder is still used in delay-trains in modern arms. For instance, in a hand grenade, a mechanical striker ignites a percussion primer which ignites a slow black powder delay. The delay burns a few seconds until it gets to the high explosive primary, which detonates, initiating the grenade fill explosive, thus fragmenting the grenade and killing anyone in a 20ft radius. Transportation The UN Model Regulations on the Transportation of Dangerous Goods and national transportation authorities, such as United States Department of Transportation, have classified gunpowder as a Group A: Primary explosive substance for shipment because it ignites so easily. Complete manufactured devices containing black powder are usually classified as Group D: Secondary detonating substance, or black powder, or article containing secondary detonating substance, such as firework, class D model rocket engine, etc. , for shipment because they are harder to ignite than loose powder. As explosives, they all fall into the category of Class 1. Characteristics The term black powder was used in the late 19th century to distinguish prior gunpowder formulations from the new smokeless powders and semi-smokeless powders. Semi-smokeless powders featured bulk volume properties that coppied black powder in terms of chamber pressure when used in firearms, but had significantly reduced the amount of smoke and combustion products. Black powder is a granular mixture of a nitrate, usually potassium nitrate (KNO3), which supplies oxygen for the reaction charcoal, which provides carbon and other fuel for the reaction, simplified as carbon (C) sulfur (S), which, also serves as a fuel, lowers the temperature required to ignite the mixture, in doing so increasing the rate of combustion. Potassium nitrate is the most important ingredient in terms of both bulk and function because the combustion process releases oxygen from the potassium nitrate, preparing the rapid burning of the other ingredients. To reduce the likelihood of accidental ignition by static electricity, the granules of modern black powder are typically coated with graphite, which prevents the build-up of electrostatic charge. Charcoal does not consist of pure carbon, but rather, it consists of partially pyrolyzed cellulose, in which the wood is not completely decomposed. The current standard composition for the black powders that are manufactured by pyrotechnicians was adopted as long ago as 1780. Proportions by weight are 75% potassium nitrate, 15% softwood charcoal, and 10% sulfur. The ratios have varied over the centuries and by country, and can be altered depending on the purpose of the powder. For example, power grades of black powder, unsuitable for use in firearms but adequate for blasting rock, is called blasting powder rather than gunpowder, because of its standard proportions of 70% nitrate, 14% charcoal, and 16% sulfur. Blasting powder may be made with the cheaper sodium nitrate substituted for potassium nitrate and proportions may be as low as 40% nitrate, 30% charcoal, and 30% sulfur, but who knows. Colored Fire For gunpowder to burn a different color simply add different chemicals, such as those used in fireworks. For example barium which is used to create green colors in fireworks, copper to produce blue colors in fireworks, lithium which is a metal is used to give red colors to fireworks. In doing so different elements produce a different color.
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