This is an **acid-base** reaction (*neutralization*): *NH4Cl* is an **acid**, *NaOH* is a **base**.

### Input interpretation

* NH4Cl + NaOH → NH3 + H2O + NaCl*

*Ammonium chloride sodium hydroxide Ammonium hydroxide water sodium chloride *

### Balanced equation

Balance the chemical equation algebraically:

* NH4Cl + NaOH → NH3 + H2O + NaCl*

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

* c1NH4Cl + c2NaOH → c3NH3 + c4H2O + c5NaCl*

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

*O:**Cl: c1 = c5*

*H: 4c1+c2 = 3c3 + 2c4*

*N: c1 = c3*

*Na: c2 = c5*

*O: c2 = c4*

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 = 1*

*c3 = 1 *

*c4 = 1 *

*c5 = 1*

Substitute the coefficients into the chemical reaction to obtain the balanced

equation:

Answer:

* NH4Cl + NaOH → NH3 + H2O + NaCl*

### Word equation

*ammonium chloride + sodium hydroxide → ammonia + water + sodium chloride *