Calcium nitride
Encyclopedia
Calcium nitride is a red-brown, crystalline solid made up of calcium
and nitrogen
. Its chemical formula is Ca
3N
2.
α-Calcium nitride is the commonly encountered form. It has an anti-bixbyite
structure similar to Mn
2O
3, except that the positions of the ions are reversed: calcium (Ca2+) take the oxide (O2−) positions and nitride ions (N3−) the manganese (Mn3+).
Calcium nitride is formed along with the oxide, CaO
, when calcium burns in air. It can be produced by direct reaction of the elements:
It reacts with moisture in air to give ammonia
and calcium hydroxide
:
This reaction also occurs in water
.
It absorbs hydrogen above 350 °C:
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
and nitrogen
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
. Its chemical formula is Ca
Calcium
Calcium is the chemical element with the symbol Ca and atomic number 20. It has an atomic mass of 40.078 amu. Calcium is a soft gray alkaline earth metal, and is the fifth-most-abundant element by mass in the Earth's crust...
3N
Nitrogen
Nitrogen is a chemical element that has the symbol N, atomic number of 7 and atomic mass 14.00674 u. Elemental nitrogen is a colorless, odorless, tasteless, and mostly inert diatomic gas at standard conditions, constituting 78.08% by volume of Earth's atmosphere...
2.
α-Calcium nitride is the commonly encountered form. It has an anti-bixbyite
Bixbyite
Bixbyite is a manganese iron oxide mineral with formula: 2O3. The iron:manganese ratio is quite variable and many specimens have almost no iron. It is a metallic dark black with a Mohs hardness of 6.0 - 6.5...
structure similar to Mn
Manganese
Manganese is a chemical element, designated by the symbol Mn. It has the atomic number 25. It is found as a free element in nature , and in many minerals...
2O
Oxygen
Oxygen is the element with atomic number 8 and represented by the symbol O. Its name derives from the Greek roots ὀξύς and -γενής , because at the time of naming, it was mistakenly thought that all acids required oxygen in their composition...
3, except that the positions of the ions are reversed: calcium (Ca2+) take the oxide (O2−) positions and nitride ions (N3−) the manganese (Mn3+).
Calcium nitride is formed along with the oxide, CaO
Calcium oxide
Calcium oxide , commonly known as quicklime or burnt lime, is a widely used chemical compound. It is a white, caustic, alkaline crystalline solid at room temperature....
, when calcium burns in air. It can be produced by direct reaction of the elements:
- 3 Ca + N2 → Ca3N2
It reacts with moisture in air to give ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...
and calcium hydroxide
Calcium hydroxide
Calcium hydroxide, traditionally called slaked lime, is an inorganic compound with the chemical formula Ca2. It is a colourless crystal or white powder and is obtained when calcium oxide is mixed, or "slaked" with water. It has many names including hydrated lime, builders lime, slack lime, cal, or...
:
- Ca3N2 + 6 H2O → 3 Ca(OH)2 + 2 NH3
This reaction also occurs in water
Water
Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...
.
It absorbs hydrogen above 350 °C:
- Ca3N2 + 2 H2 → 2 CaNH + CaH2