3 ms·

Gunpowder still requires an oxidizer, it just happens to be mixed in. The potassium nitrate is the oxidizer, KN03, whereas the sulphur and charcoal are the fuel

Gunpowder still requires an oxidizer, it just happens to be mixed in. The potassium nitrate is the oxidizer, KN03, whereas the sulphur and charcoal are the fuels that burn. Pretty much any combustion requires a molecule with oxygen to accept the electrons: exceptions exist with halogens like chlorine… but these are still called “oxidizers” So saying hydrogen doesn’t burn without an oxidizer still makes little sense. Hydrogen will combust with either oxygen or chlorine for example, both oxidizers. Without those then nothing happens because nothing can combust without an oxidizer… You may just not realize the oxidizer is mixed with the fuel.

jandrewrogers 5y ago
Technically speaking, sulfur is an oxidizer in gunpowder, not fuel. Sulfur is even in the same elemental group as oxygen. Sulfur is commonly used as an oxidizer for metal fuels. In the case of gunpowder, that would be the potassium in potassium nitrate.
- crazydoggers 5y ago
  That’s not correct. (Sulfur can be an oxidizer in some reactions as you mention, but not in gunpowder where it acts as the fuel) https://www.wikipedia.org/wiki/Gunpowder#Components https://www.wikipedia.org/wiki/Gunpowder#Components Potassium nitrate is the most important ingredient in terms of both bulk and function because the combustion process releases oxygen from the potassium nitrate, promoting the rapid burning of the other ingredients Sulfur's main role in gunpowder is to decrease the ignition temperature. A sample reaction for sulfur-free gunpowder would be: 6 KNO3 + C7H4O → 3 K2CO3 + 4 CO2 + 2 H2O + 3 N2
  - jandrewrogers 5y ago
    Nothing you’ve stated contradicts my point. You are also misunderstanding the chemistry in the passage you quoted. Sulfur is commonly used to bootstrap exothermic reactions, largely based on its strong affinity for oxidizing metals with relatively low activation energy. In gunpowder, you need the potassium nitrate to release the “nitrate” part so that it can oxidize the carbon but for that to happen you need to offer potassium something more thermodynamically attractive to bind to. Charcoal (carbon) cannot serve that purpose. Sulfur provides that thermodynamically attractive outlet for potassium such that it will happily release the nitrate. Sulfur, in this case, would be termed a “sensitizer” but the mechanism of action is as a metal oxidizer. Sulfur/metal complexes are often used to bootstrap hard-to-ignite things such as thermites. There are many metal oxidizer salts that become so sensitized in the presence of sulfur that they become dangerously unstable. In the case of potassium nitrate, it becomes more sensitized but still stable enough to be useful. For most real industrial applications, metal oxidizer salts have long been replaced with ammonium oxidizer salts which don’t have any metals to worry about. The “sulfur-free” formulation uses an organic fuel (gunpowder does not), which provides alternative potassium sinks thereby obviating the need for sulfur.
    - crazydoggers 5y ago
      > You are also misunderstanding the chemistry in the passage you quoted. I’m not. I’ll give the benefit of the doubt we have a miscommunication though. > Technically speaking, sulfur is an oxidizer in gunpowder, not fuel. This initial statement makes it sound like you were claiming that the potassium nitrate is not the primary oxidizer in the combustion. It is the potassium nitrate’s role which is the oxidizer and not the fuel. And yes, sulfur attracts the potassium, and aids in the reaction, but it’s role is also as fuel, which you incorrectly stated it was not. Again, from wikipedia: sulfur (S), which, while also serving as a fuel, lowers the temperature required to ignite the mixture, thereby increasing the rate of combustion. [1] [1]https://en.m.wikipedia.org/wiki/Gunpowder#Components https://en.m.wikipedia.org/wiki/Gunpowder#Components And Fuel: A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. Sulfur itself can be burned. Potassium nitrate cannot. In fact if you add sulfur to potassium nitrate the sulfur can act as the reducing agent and you’ll get sulfur dioxide. 4KNO3+5S⟶2K2O+5SO2+2N2 To categorize sulfur over the potassium nitrate in the role of oxidizers doesn’t make a lot of sense, which is how I interpreted your initial statement, perhaps wrongly. Gunpowder (specifically black powder) works in a vacuum because of the potassium nitrate, not because of the sulfur. You can have gunpowder without sulfur, but it’s not going to work without the potassium nitrate.

jandrewrogers 5y ago

Technically speaking, sulfur is an oxidizer in gunpowder, not fuel. Sulfur is even in the same elemental group as oxygen. Sulfur is commonly used as an oxidizer for metal fuels. In the case of gunpowder, that would be the potassium in potassium nitrate.

crazydoggers 5y ago
That’s not correct. (Sulfur can be an oxidizer in some reactions as you mention, but not in gunpowder where it acts as the fuel) https://www.wikipedia.org/wiki/Gunpowder#Components https://www.wikipedia.org/wiki/Gunpowder#Components Potassium nitrate is the most important ingredient in terms of both bulk and function because the combustion process releases oxygen from the potassium nitrate, promoting the rapid burning of the other ingredients Sulfur's main role in gunpowder is to decrease the ignition temperature. A sample reaction for sulfur-free gunpowder would be: 6 KNO3 + C7H4O → 3 K2CO3 + 4 CO2 + 2 H2O + 3 N2
- jandrewrogers 5y ago
  Nothing you’ve stated contradicts my point. You are also misunderstanding the chemistry in the passage you quoted. Sulfur is commonly used to bootstrap exothermic reactions, largely based on its strong affinity for oxidizing metals with relatively low activation energy. In gunpowder, you need the potassium nitrate to release the “nitrate” part so that it can oxidize the carbon but for that to happen you need to offer potassium something more thermodynamically attractive to bind to. Charcoal (carbon) cannot serve that purpose. Sulfur provides that thermodynamically attractive outlet for potassium such that it will happily release the nitrate. Sulfur, in this case, would be termed a “sensitizer” but the mechanism of action is as a metal oxidizer. Sulfur/metal complexes are often used to bootstrap hard-to-ignite things such as thermites. There are many metal oxidizer salts that become so sensitized in the presence of sulfur that they become dangerously unstable. In the case of potassium nitrate, it becomes more sensitized but still stable enough to be useful. For most real industrial applications, metal oxidizer salts have long been replaced with ammonium oxidizer salts which don’t have any metals to worry about. The “sulfur-free” formulation uses an organic fuel (gunpowder does not), which provides alternative potassium sinks thereby obviating the need for sulfur.
  - crazydoggers 5y ago
    > You are also misunderstanding the chemistry in the passage you quoted. I’m not. I’ll give the benefit of the doubt we have a miscommunication though. > Technically speaking, sulfur is an oxidizer in gunpowder, not fuel. This initial statement makes it sound like you were claiming that the potassium nitrate is not the primary oxidizer in the combustion. It is the potassium nitrate’s role which is the oxidizer and not the fuel. And yes, sulfur attracts the potassium, and aids in the reaction, but it’s role is also as fuel, which you incorrectly stated it was not. Again, from wikipedia: sulfur (S), which, while also serving as a fuel, lowers the temperature required to ignite the mixture, thereby increasing the rate of combustion. [1] [1]https://en.m.wikipedia.org/wiki/Gunpowder#Components https://en.m.wikipedia.org/wiki/Gunpowder#Components And Fuel: A fuel is any material that can be made to react with other substances so that it releases energy as thermal energy or to be used for work. Sulfur itself can be burned. Potassium nitrate cannot. In fact if you add sulfur to potassium nitrate the sulfur can act as the reducing agent and you’ll get sulfur dioxide. 4KNO3+5S⟶2K2O+5SO2+2N2 To categorize sulfur over the potassium nitrate in the role of oxidizers doesn’t make a lot of sense, which is how I interpreted your initial statement, perhaps wrongly. Gunpowder (specifically black powder) works in a vacuum because of the potassium nitrate, not because of the sulfur. You can have gunpowder without sulfur, but it’s not going to work without the potassium nitrate.