Question

Potassium nitrate is called:
A.Mohr's salt
B.Indian saltpetre
C.Gypsum
D.Chile saltpetre

Answer 1

Potassium nitrate $\left( {KN{O_3}} \right)$ is one of many nitrogen containing compounds collectively known as saltpetre or saltpetre. Some of the major uses of potassium nitrate are in fertilizers, tree stump removal, rocket propellants and fireworks.

Complete step by step answer:
Ammonium iron (II) sulphate is also known as Mohr’s salt. It is the inorganic compound with the formula $\left( {N{H_4}} \right)2Fe{\left( {S{O_4}} \right)_2}{\left( {{H_2}O} \right)_6}$. It contains two different cations- $F{e^{2 + }}$ and $N{H^{4 + }}$. It is categorised as a double salt of ammonium sulphate and ferrous sulphate.
Gypsum is a soft sulphate mineral composed of calcium sulphate dihydrate, with the chemical formula $CaS{O_4}.2{H_2}O$.
Sodium nitrate is a chemical compound which has the formula $NaN{O_3}$. This alkali metal nitrate salt is also called Chile saltpetre.
Potassium nitrate $\left( {KN{O_3}} \right)$ is also called Indian saltpetre. This is because it is one of the many nitrogen-containing compounds and is most important as a crude salt in India. It is a major constituent of gunpowder. Saltpetre means “salt of the rock”, it is named so because it is found as an incrustation. Potassium nitrate compound is also called nitre.
The three main components of potassium nitrate are potassium, nitrogen, and oxygen which are primarily used in gunpowder to make explosives, it is also used in fireworks, hand-grenade fuses, and artillery shell primers too.

Therefore, the correct answer is option (B).

Note: Potassium nitrate occurs as crusts on the surface of the Earth, on walls and rocks, and in caves. It forms in certain soils in India, Italy, Egypt, Iran, and Spain. Breathing of $KN{O_3}$ can lead to irritation of the nose and throat causing sneezing and coughing. High levels of interaction with $KN{O_3}$ can lead to the ability of the blood to carry Oxygen causing headache, fatigue, dizziness, and a blue colour to the skin and lips.