carbon black is used for colouring things like car tyresWhat is used carbon black powder ?
mainly carben black powerded uses in to the
highly explosive mattrs.
it is not containing the oxygen moleculs.
it causes higher illness with the living particls
Common uses
The most common use [70%] of carbon black is as a pigment and reinforcing phase in automobile tires. Carbon black also helps conduct heat away from the tread and belt area of the tire, reducing thermal damage and increasing tire life. Carbon black particles are also employed in some radar absorbent materials and in printer toner.
Total production is about 8.1 million tonnes (2006)[1]. About 20% of world production goes into belts, hoses, and other rubber goods. The balance is used in inks and as a pigment for products other than tires.
Carbon black from vegetable origin is used as a food coloring , in Europe known as additive E153.
Carbon Black powder is a granular mixture of
a nitrate—typically saltpetre (KNO3)—which supplies the reaction with oxygen charcoal, which provides fuel for the reaction in the form of carbon (C) sulphur (S), which is also a fuel, lowers the temperature of ignition and helps increase the speed of combustion Saltpetre is the most important ingredient in terms of both bulk and function because the oxygen released by the combustion of saltpetre promotes the rapid burning of the other ingredients.[1] To reduce the likelihood of accidental ignition by static electricity, the granules of modern black powder are typically coated with graphite, which prevents build-up of electrostatic charge.
The optimum proportions for gunpowder are: 74.64% saltpetre, 13.51% charcoal, and 11.85% sulfur (by weight). The current standard for black powder manufactured by pyrotechnicians today is 75% potassium nitrate, 15% softwood charcoal and 10% sulfur; it appears to have been adopted as far back as 1780.[2] These ratios have varied over the centuries and can be altered somewhat depending on the purpose of the powder.
The burn rate of black powder can be changed by corning. Corning is a process which first compresses the fine black powder meal into blocks with a fixed density (1.7 g/cm³). The blocks are then broken up into granules. These granules are then sorted by size to give the various grades of black powder. Standard, USA, grades of black powder run from the coarse Fg grade used in large bore rifles and small cannon though FFg (medium and smallbore rifles), FFFg (pistols), and FFFFg (smallbore, short pistols and priming flintlocks). In the United Kingdom, the gunpowder grains are categorised by mesh size: the BSS sieve mesh size, being the largest mesh size on which no grains were retained. Recognised grain sizes are Gunpowder: 'G 7', 'G 20', 'G 40' and 'G 90'.
A simple, commonly cited, chemical equation for the combustion of black powder is:
2 KNO3 + S + 3 C → K2S + N2 + 3 CO2
A more accurate, but still simplified, equation is:[3]
10 KNO3 + 3 S + 8 C → 2 K2CO3 + 3 K2SO4 + 6 CO2 + 5 N2
The products of burning do not follow any simple equation. One study's results showed it produced (in order of descending quantities): 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, 1.11% water.
Black powder formulations where the nitrate used is sodium nitrate tend to be hygroscopic, unlike black powders where the nitrate used is saltpetre. Because of this, black powder which uses saltpetre can be stored unsealed and remain viable for centuries provided no liquid water is ever introduced; muzzleloaders have been known to fire after hanging on a wall for decades in a loaded state, provided they remained dry. By contrast, powder which uses sodium nitrate, which is typically intended for blasting, must be sealed from moisture in the air to remain stable for long periods of time.
Advantages of black powder
Smokeless powder requires precise loading of the charge to prevent damage due to overloading. With black powder, though such damage is still possible, loading can generally be carried out using volumetric measures rather than precise weight.
Generally, high explosives are preferred for shattering rock; however, 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 stone such as granite and marble.
Black powder is well suited for blank rounds, signal flares, and rescue line launches.
Gunpowder can be used to make fireworks by mixing with chemical compounds that produce the desired color.
Disadvantages of black powder
Black powder has relatively low energy density compared to modern smokeless powders and produces a thick smoke which can impair aiming or reveal a shooter's position.
Combustion converts less than half the mass of black powder to gas; the rest ends up as a thick layer of soot inside the barrel. In addition to being a nuisance, the residue from burnt black powder is hygroscopic and an anhydrous caustic substance. When moisture from the air is absorbed, the potassium oxide or sodium oxide turns into hydroxide, which will corrode wrought iron or steel gun barrels. Black powder arms must be well cleaned both inside and out to remove the residue.
The United States Department of Transportation has classified black powder as a ';Class A High Explosive'; for shipment because it ignites so easily, even though it is not a high explosive at all. Complete manufactured devices containing black powder are usually classified as ';Class C Firework';, ';Class C Model Rocket Engine';, etc. for shipment because they are harder to ignite than loose powder.
Gunpowder
Check : Wikipedia
in the ancient time when black powder was still used in warfare, people get carbon from charcoal.
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