Chapter 9 Balancing Equations Part 2

Balancing Equation Strategy Balance elements that occur in only one compound on each side first. Balance free elements last. Balance unchanged polyatomic ions as groups. Fractional coefficients are acceptable but must be cleared at the end using multiplication.

C 6 H 14 O 4 + O 2 → CO 2 + H 2 O6 2. Balance H. 2 C 6 H 14 O O 2 → 12 CO H 2 O 4. Multiply by two Balancing Example 3. Balance O. and check all elements. Chemical Equation: 1. Balance C. 6 7

Ca 3 (PO 4 ) 2 + H 2 SO 4 → CaSO 4 + H 3 PO 4 In this equation, the polyatomic ions do not break up. Instead of counting individual atoms, polyatomic ion groups may be counted.

Ca 3 (PO 4 ) 2 + H 2 SO 4 → CaSO 4 + H 3 PO 4

Cu + H 2 SO 4 → CuSO 4 + H 2 O + SO 2 The sulfate group breaks up. Each atom must be counted individually.

Cu + H 2 SO 4 → CuSO 4 + H 2 O + SO 2

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”