Potassium Nitrate – KNO3
What is Potassium Nitrate (KNO3)?
KNO3 is a chemical compound with chemical name Potassium Nitrate.
Potassium nitrate also called saltpeter or niter, a white solid soluble in water formed by fractional crystallization of sodium nitrate and potassium chloride solutions. It occurs naturally as niter in rocks in India, South Africa and Brazil. When heated it decomposes to give the nitrite and oxygen. Unlike sodium nitrate it is non-deliquescent. Potassium nitrate is used in gunpowder, fertilizers and in the laboratory preparation of nitric acid.
Potassium nitrate is the most common desensitizing agent in over-the-counter dentifrices. At a concentration of 5%, potassium nitrate in conjunction with sodium or monofluorophosphate fluoride significantly reduces symptoms within 2 weeks of daily use. Potassium ions penetrate the length of the dentinal tubule and block repolarization of the nerve ending.
Frequent and regular application of a potassium nitrate dentifrice is necessary to avoid recurrence of symptoms, maintain a high abundance of extracellular potassium ions, and maintain the inter dental nerves in a hyperpolarized state. Potassium nitrate, often called saltpeter, occurs as an efflorescence in caverns and on soils in arid regions.
Properties of Potassium Nitrate – KNO3
| KNO3 | Potassium Nitrate |
| Molecular Weight/ Molar Mass | 101.1032 g/mol |
| Density | 2.109 g/cm3 |
| Boiling Point | 400 °C |
| Melting Point | 334 °C |
Potassium Nitrate (KNO3 ) Uses
- It is used as a form of fertilizer as it contains all the macronutrients needed for the plants to grow.
- It is used as gunpowder in explosives such as bombs, grenades, etc.
- Used in the manufacturing and production of cigarettes.
- It is used extensively used in the preservation of hides
- It has medicinal applications such as a diuretic in medicine
- Used in toothpaste to make the teeth less sensitive to pain
- Used in the food industry to preserve meat against microbial agents
Potassium Nitrate (KNO3 ) Health Hazards
- Potential exposure – Potassium Nitrate is used in chemical analysis, as a food additive in fertilizers in medications as a vasodilator and as antidote for cyanide poisoning.
- Short term exposure – Potassium nitrate can affect when breathed in. Contact can cause eye and skin burns. Breathing the dust or mist can irritate the nose, throat and lungs and may cause coughing with phlegm. Higher exposures can cause pulmonary edema, a medical emergency that can be delayed for several hours. This can cause death.
- Long term exposure – Repeated skin contact causes dermatitis, drying and cracking. May cause lung irritation, bronchitis may develop. There is limited evidence that potassium nitrite may damage the developing fetus.
- Medical surveillance – If symptoms develop or overexposure is suspected, the following may be useful, blood test for methemoglobin. Lung function tests. Consider chest X-ray after acute overexposure.
- Potassium nitrate is an inorganic salt which has a molecular KNO3 formula. This is a common form of nitrate which has been used for numerous uses as a component, including agricultural preservatives, fertilizers, tree stump removal, rocket propellants, which fireworks.
- Potassium nitrate is a common active ingredient that exerts an anti-sensitive effect in toothpaste. It offers enhanced protection against the painful sensitivity of the teeth to ice, sun, acids, sweets or touch.