While technology is neutral, people definitely are not, which is, I think, a pretty good argument against the right to bear arms, or nations nuclear weapons. …Today. Back in the old west, however, you may have legitimately needed to defend yourself against zombie aboriginal peoples:
“The Stand” was my second assignment of Bobby Chiu’s digital painting course (www.schoolism.com). My homework was to colour in a black and white painting provided by Bobby (inset). In theory, I can now colour anything; old photos, low resolution scans, and, most importantly to me, homemade black and white paintings like “Flex”. Although I tried to stay within the lines, you can see where I was sloppy by the telltale “halo” edging bald cowboy’s hair rim. That mistake, and maybe poor colour choices, got me 4 out of 5 stars for this second assignment.
The educational tie-in to this painting, I’ve decided, is – to continue on the theme of the Haber process – explosives, specifically the propellant used in these cowboys’ firearms, gunpowder. Most authoritative modern views attribute the discovery of gunpowder to 9th century AD Chinese who, in their search for the potion of immortality, may have stumbled across the right ratio of potassium nitrate, sulfur and carbon (15:3:2, respectively, by weight (3)) to make a bang (1). The philosopher John Bate referred to the three components of the mechanical mixture as, “the body” (charcoal), “the life” (sulfur), and “the soul” (potassium nitrate) (2).
“The Body”
Carbon (C), is obtained in the form of charcoal, which is almost pure carbon. The timber is selected carefully: dogwood for rapid-burning small grains (shotguns), willow and alder for slower-burning coarse grains (blasting), and beach and birch make discount gunpowder for everyday usage (cap guns?), all of which has led to substantial deforestation in many parts of the world (1).
“The Life”
Sulfur (S) is a yellow solid known biblically as brimstone, and probably got its reputation of “raining upon the wicked” because the deposits easiest to mine were in volcanic regions (2). …And it smells terrible when it’s burned. My brother came across sulfur blocks while on a tour in Chile:
The educational tie-in to this painting, I’ve decided, is – to continue on the theme of the Haber process – explosives, specifically the propellant used in these cowboys’ firearms, gunpowder. Most authoritative modern views attribute the discovery of gunpowder to 9th century AD Chinese who, in their search for the potion of immortality, may have stumbled across the right ratio of potassium nitrate, sulfur and carbon (15:3:2, respectively, by weight (3)) to make a bang (1). The philosopher John Bate referred to the three components of the mechanical mixture as, “the body” (charcoal), “the life” (sulfur), and “the soul” (potassium nitrate) (2).
“The Body”
Carbon (C), is obtained in the form of charcoal, which is almost pure carbon. The timber is selected carefully: dogwood for rapid-burning small grains (shotguns), willow and alder for slower-burning coarse grains (blasting), and beach and birch make discount gunpowder for everyday usage (cap guns?), all of which has led to substantial deforestation in many parts of the world (1).
“The Life”
Sulfur (S) is a yellow solid known biblically as brimstone, and probably got its reputation of “raining upon the wicked” because the deposits easiest to mine were in volcanic regions (2). …And it smells terrible when it’s burned. My brother came across sulfur blocks while on a tour in Chile:
although, if hue is any indication, this rock is quite low in sulfur content.
“The Soul”
Potassium nitrate, (KNO3, or saltpeter, from the Latin “sal petrae” literally meaning, “salt of the stone”), occurs naturally as a white efflorescence where there is an abundance of nitrogenous organic matter, typically from decomposing animal or vegetable matter. Unsurprisingly then, a rich source of saltpeter is sewage waste. Since maintaining sufficient supplies of saltpeter for explosives production was a matter of national security, especially during wartime (which was a lot of the time in Europe), extreme measures were taken in the past to ensure supply. In 1626 England, King Charles I commanded his subjects to, “keep and preserve in some convenient vessels or receptacles fit for the purpose, all the urine of man during the whole year, and all the stale of beasts which they can save” (2). And in the following decade, he additionally decided that house and barns floors were to “lie open with good and mellow earth, apt to breed an increase of saltpeter” (2); a couple of gut-churning laws that would certainly violate public health code today. The result was that house and barn floors produced thick crusts rich in nitrates, which were dug up, converted to potassium nitrate through counter ion exchange in water, and then purified by recrystallization, in essence.
Although black powder is made up of three components, it has been described as working together like a single compound (4). Saltpeter undergoes a rhombic to trigonal solid-solid transition at 130 C, which ‘loosens’ the solid, effecting to make it more reactive and ignitable (4). In addition to acting as a fuel, the finely ground charcoal provides a high surface area for adsorption of gases given off during early chemical reactions that are consumed in subsequent reactions (4). On the other hand, the soft sulfur melts at relatively low temperatures and exhibits a pseudo-plastic behaviour that ‘glues’ the powder together, so that it lowers the activation energy, and functions as a unit (4). The overall process can be summed up broadly as
“The Soul”
Potassium nitrate, (KNO3, or saltpeter, from the Latin “sal petrae” literally meaning, “salt of the stone”), occurs naturally as a white efflorescence where there is an abundance of nitrogenous organic matter, typically from decomposing animal or vegetable matter. Unsurprisingly then, a rich source of saltpeter is sewage waste. Since maintaining sufficient supplies of saltpeter for explosives production was a matter of national security, especially during wartime (which was a lot of the time in Europe), extreme measures were taken in the past to ensure supply. In 1626 England, King Charles I commanded his subjects to, “keep and preserve in some convenient vessels or receptacles fit for the purpose, all the urine of man during the whole year, and all the stale of beasts which they can save” (2). And in the following decade, he additionally decided that house and barns floors were to “lie open with good and mellow earth, apt to breed an increase of saltpeter” (2); a couple of gut-churning laws that would certainly violate public health code today. The result was that house and barn floors produced thick crusts rich in nitrates, which were dug up, converted to potassium nitrate through counter ion exchange in water, and then purified by recrystallization, in essence.
Although black powder is made up of three components, it has been described as working together like a single compound (4). Saltpeter undergoes a rhombic to trigonal solid-solid transition at 130 C, which ‘loosens’ the solid, effecting to make it more reactive and ignitable (4). In addition to acting as a fuel, the finely ground charcoal provides a high surface area for adsorption of gases given off during early chemical reactions that are consumed in subsequent reactions (4). On the other hand, the soft sulfur melts at relatively low temperatures and exhibits a pseudo-plastic behaviour that ‘glues’ the powder together, so that it lowers the activation energy, and functions as a unit (4). The overall process can be summed up broadly as
To put the equation into perspective, note that the reaction produces 8 moles of gas from 12 moles of solid black powder, which corresponds to 3L of gas per gram of black powder. Furthermore, the temperature of the reaction can be calculated from standard heats of formation to be -1688 kJ/mol, or a theoretical flame of 3070 K (2800 C, 5000 F) (4). Underscoring why you don’t want to try this at home. Ideal for lobbing into a hoard of zombies, though.Many other facts and fascinating anecdotes from the history of gunpowder can be found inside these following references:
1. Brown, G. I. (1998). “The big bang: A history of explosives.” Sutton Publishing Limited
2. Brown, S. R. (2005). “A most damnable invention: Dynamite, nitrates, and the making of the modern world.” Viking Canada
3. von Maltitz, I. (2003). “Black powder manufacturing, testing & optimizing.” American Fireworks News
4. Russell, M. S. (2000). “The chemistry of fireworks.” Royal Society of Chemistry Paperbacks
