Chapter 9Chapter 9Balancing EquationsBalancing Equations

Part 2Part 2

Balancing Equation Strategy

• Balance elements that occur in only one compound on each side first.

• Balance free elements last.

• Balance unchanged polyatomics as groups.

• Fractional coefficients are acceptable and can be cleared at the end by multiplication.

152 6 7C6H14O4 + O2 → CO2 + H2O 6

2. Balance H.

2 C6H14O4 + 15 O2 → 12 CO2 + 14 H2O

4. Multiply by two

Balancing Example

3. Balance O.

and check all elements.

Chemical Equation:

1. Balance C.

6 7

Ca3(PO4)2 + H2SO4 → CaSO4 + H3PO4

• In this equation, the polyatomic ions do not break up.

• Instead of counting individual atoms, polyatomic ion groups may be counted.

Ca3(PO4)2 + H2SO4 → CaSO4 + H3PO4

Cu + H2SO4 → CuSO4 + H2O + SO2

• The sulfate group breaks up. Each atom must be counted individually.

Cu + H2SO4 → CuSO4 + H2O + SO2

Balancing Equations

• This method of balancing equations is the inspection method.

• The method is trial and error.

• You need to Practice.

Homework

• Worksheet: “Balancing Equations Ch. 9”