No. 1 Powder
- a nitrate, typically 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, while also a fuel, lowers the temperature of ignition and increases the speed 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, promoting the rapid burning of the other ingredients.
On Roundworld, the current standard composition for black powder manufactured by pyrotechnicians was adopted as long ago as 1780. Proportions by weight are 75% potassium nitrate, 15% softwood charcoal, and 10% sulfur
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:
- 10 KNO3 + 3 S + 8 C → 2 K2CO3 + 3 K2SO4 + 6 CO2 + 5 N2.