Uploaded July 2015 | Updated September 2026, 3 weeks ago
A pure sample of hydrated calcium nitrate appears crystalline and glossy because of the water of crystallisation.
As you first gently heat the crystals, the water of crystallisation escapes as water vapour, condensing along the sides of the test-tube as water droplets. This forms a highly concentrated solution of calcium nitrate, which boils.
Upon further gentle heating, all of the water of crystallisation is eventually removed, leaving behind a powdery anhydrous form of calcium nitrate.
Switching to strong heating, the calcium nitrate soon melts and decomposes into calcium oxide, brown nitrogen dioxide gas and oxygen gas.
The oxygen gas relights a glowing splint, while the brown nitrogen gas is acidic, and turns moist blue litmus paper red.
A pure sample of hydrated calcium nitrate appears crystalline and glossy because of the water of crystallisation.
As you first gently heat the crystals, the water of crystallisation escapes as water vapour, condensing along the sides of the test-tube as water droplets. This forms a highly concentrated solution of calcium nitrate, which boils.
Upon further gentle heating, all of the water of crystallisation is eventually removed, leaving behind a powdery anhydrous form of calcium nitrate.
Switching to strong heating, the calcium nitrate soon melts and decomposes into calcium oxide, brown nitrogen dioxide gas and oxygen gas.
The oxygen gas relights a glowing splint, while the brown nitrogen gas is acidic, and turns moist blue litmus paper red.
