Question

Name a nitrate which produces oxygen as the only gas.

Answer 1

Hint : It is a white deliquescent solid which is soluble in water. It is an alkali metal nitrate salt which is also known as Chile saltpeter. This compound can be synthesized industrially by neutralizing nitric acid with sodium carbonate or sodium bicarbonate or even by neutralizing it with sodium hydroxide. It can be used to prepare nitric acid and can also be used as a preservative for foods.

Complete Step By Step Answer:
When sodium nitrate is heated it undergoes decomposition reaction to form sodium nitrite and odorless and colorless oxygen gas.
$2NaN{O_3} \to 2NaN{O_2} + {O_2}$
Hence, we can conclude that sodium nitrate is the nitrate which produces oxygen as the only gas.

Additional Information:
Sodium nitrate is non - combustible but it can accelerate the burning of various combustible materials. If large amounts are involved in fire or the combustible material is finely divided an explosion may result. It can explode under prolonged exposure to fire or heat. Toxic oxides of nitrogen will be produced when sodium nitrate is exposed to fires. It is also used in solid propellants, fertilizers and explosives. Sodium nitrate is said to have carcinogenic effects on humans. It acts as a strong oxidizing agent. Sodium nitrate consists of two crystal structures which are rhombohedral and trigonal.
This compound is said to be highly soluble in ammonia. When dissolved in water, sodium nitrate dissociates into sodium and nitrate ion.

Note :
Potassium nitrate is also capable of producing oxygen gas when it is heated by undergoing decomposition. It produces potassium nitrite also along with the colorless and odorless oxygen.
$2KN{O_3} \to 2KN{O_2} + {O_2}$ .