CaCN2 - CALCIUM CYANAMIDE

Properties of calcium cyanamide:

White (technical product - dark-gray because of the impurity of coal). Volatile, melts without decomposition under pressure of N2, at calcination it is decomposes. It soluble in cold water (hydrolysis on the anion). Completely decomposed by hot water. It reacts with acids. In wet soil under influence of bacteria decomposes slowly with release of ammonia.


Molar mass g/mol 80.10
Density g/cm3 2.29
Melting point °C 1300

Methods for preparation of calcium cyanamide:

CaO + 2HCN = CaCN2 + CO + H2 (700° C).

CaCO3 + 2NH3 = CaCN2 + 3H2O (700-900° C).

CaC2 + N2 = CaCN2 + C(graphite) [1100-1150° C].

2CaC2 + N2 + 2NH3 = 2CaCN2 + C2H2 + 2H2 (800-900° C).


Chemical reactions with calcium cyanamide:

CaCN2 = CaC2 + N2 (above 1150° C).

CaCN2 + 6H2O(cold) = [Ca(H2O)6](2+) + CN2(2-),

CN2(2-) + H2O = HCN(-)2 + OH(-).

CaCN2 + 3H2O(hot) = Ca(OH)2 + C(NH2)2O (70° C).

CaCN2 + 2H2O(vapor) = CaCO3 + 2NH3 (300° C).

CaCN2 + H2SO4(diluted) = CaSO4↓ + H2CN2.

CaCN2 + CO2 + H2O = CaCO3↓ + H2CN2.

CaCN2 + 3H2 = Ca + C(graphite) + 2NH3 (550-650° C).

2CaCN2 + 3O2 = 2CaCO3 + 2N2 (420-450° C).


 

Did you know?

A pure element can take many forms. For example, diamond and graphite both are forms of pure carbon.