1. Ca(OH)2 + (NH4)2SO4 → CaSO4 + NH3 + H2O
Bell Ringer
Balance the following chemical equation:
Ca(OH)2 + (NH4)2SO4 → CaSO4 + NH3 + H2O
Ca(OH)2 + (NH4)2SO4 → CaSO4 + 2NH3 + 2H2O

2. Algebraic Method for Balancing Chemical Equation

3. Algebraic method
EG. C4H10 + O CO2 + H20
put unknown coefficients in front of each molecular species in the equation:
xC4H yO zCO2 + wH20
write down the balance conditions for each element in terms of the unknowns (x,y,z,w).
Carbon balance:
4x= z
Hydrogen balance condition is:
10x=2w

4. xC4H yO zCO2 + wH20
oxygen balance condition gives:
2y= 2z + w
We should recognize that chemical equations specify relative amounts of reactants and products. Thus, one of the coefficients is arbitrary.
We may take one of the coefficients to be 1. (according to convenience)
Assume x= 1,
4x= z therefore, z= 4
10x=2w therefore, w= 5
from oxygen balance condition, y= 2z + w
2y = 2 x 4 + 5
y= 13/2
Thus, the balanced equation could be written as :
C4H /2 O CO2 + 5H20

5. Multiply through the equation by 2 on both sides (it can be treated as an algebraic equation in this way)
C4H /2 O CO2 + 5H20
2C4H O CO2 + 10H20