### Word equation

*tin(II) chloride + water → tin(II) hydroxide + hydrogen chloride*

### Input interpretation

*SnCl2 + 2H2O → Sn(OH)2 + 2HCl*

*tin(II) chloride water tin(II) hydroxide hydrogen chloride*

### Balanced equation

Balance the chemical equation algebraically:

*SnCl2 + 2H2O → Sn(OH)2 + 2HCl*

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

*c1 SnCl2 + c2 2H2O → c3 Sn(OH)2 + c4 2HCl*

Set the number of atoms in the reactants equal to the number of atoms in the products for **Cl, Sn, H **and **O**:

*Cl: **2c1= c4*

*Sn: **c1 = c3*

*H: **2c2 = 2c3 + c4*

*O:** c2=2c3*

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=2

c3 = 1

c4=2

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

**Answer**:

*SnCl2 + 2H2O → Sn(OH)2 + 2HCl*