What happens when potassium nitrate is heated?

Question

What is the chemical reaction and chemical breakdown of the potassium nitrate if heated?

Answer 1

On heating potassium nitrate, it melts and decomposes to potassium nitrite, an inorganic compound and oxygen gas. This is a chemical change that gives a pale yellow residue. The temperature required to melt is in between 550 to 790^o C.

2KNO₂   ⇔ 2KNO₂ + O₂

_{Potassium nitrate used near fire hazards in a storage form.}

_{Also, potassium nitrate can be oxidized to potassium nitrite with the help of nitrifying bacteria (nitrobacter) and the process is also known as Nitrosomas.}