potassium nitrate solution, KNO3, is an alkali metal nitrate that is soluble in water. This nitrate has a white to grayish appearance and is odorless when in solution.
It contains the soft, light and silvery metal potassium, oxygen and nitrogen ions (K+ and NO3-). When heated or decomposed it releases a lot of oxygen.
This chemical is a major component of black powder, fireworks and fertilizer. It is also used as an antidote for cyanide poisoning and is a vasodilator.
A crystalline form of the compound is produced by heating a mixture of sodium nitrate and potassium chloride to 115 degrees C and then cooling it until the potassium nitrate crystallizes out of the mother liquor. The nitric acid is then added to restore the initial conditions and the cycle is repeated.
The resulting potassium nitrate is then treated with hydrochloric acid to give potassium nitric acid. This is then reacted with phosphoric acid to give a phosphatic solution that may be separated by treating it with hot nitric acid, until the phosphate precipitates from the resulting acid.
It is a useful chemical to have around when dealing with dentin hypersensitivity, as it can be burnished to desensitize teeth at a higher and more effective level than DMI alone. In a study of periodontal patients with hypersensitive dentin, using a visual analogue scale and the participants acting as their own control, a saturated potassium nitrate solution was found to reduce pain significantly when compared to burnishing the dentin with DMI.