Word equation

magnesium nitride + hydrogen chloride → magnesium chloride + ammonia

Input interpretation

Mg3N2 + HCl → MgCl2 + NH3

Magnesium nitride hydrogen magnesium chloride ammonia chloride

Balanced equation

Balance the chemical equation algebraically: 

Mg3N2 + HCl → MgCl2 + NH3

Add stoichiometric coefficients, c;, to the reactants and products:

c1 Mg3N2 + c2HCl → c3MgCl2 + c4 NH3

Set the number of atoms in the reactants equal to the number of atoms in the products for Mg, N, Cl and H:

Mg: 3c1 = c3

N: 2c1= c4

Cl: c2 = 2c3

H: c2 = 3c4

Since the coefficients are relative quantities and underdetermined, choose a coefficient to set arbitrarily. To keep the coefficients small, the arbitrary value is ordinarily one. For instance, set c1 = 1 and solve the system of equations for the remaining coefficients:

c1=1

c2=6

c3=3

c4=2

Substitute the coefficients into the chemical reaction to obtain the balanced equation:

Answer:

Mg3N2 + HCl → MgCl2 + NH3