Oxidation numbers:

1
Oxidation numbers

• Ca
• Ca2
• Al
• AlPO4
• NaHCO3
• F2

2

• Reaction Ag2S Al ? ?

Ag2S Al ? Al2S3 Ag
3 2 6
3

• Synthesis4Fe 3O2 ? 2 Fe2O3
• Decomposition 2 HgO ? 2 Hg O2
• Single Replacement MgCuSO4 ? MgSO4Cu
• Combustion C3H8 5O2? 3CO2 4H2O

4
Activity Series

• ranks metals according to their relative
  reactivity.
• (p. 288)

5
Redox Reactions

• Corrosion
• Bleaching
• Electrochemical
• Fuels Explosives
• Photography

6
Balancing Redox Equations

• electrons lost by oxidized substance of
  electrons gained in reduced substance.

7
Oxidation method

• 1. Assign oxidation numbers to all atoms.

8

• 2. Connect changing elements with line show
  how oxidation changes.

9

• 3. Choose coefficients that will balance the
  change in electrons.

10

• 4. Finish balancing the equation.

11

• 5. Add necessary water or water ions to balance
  the equation.

12
Problem

• Balance this reaction of chloride and
  permanganate ions in an acidic solution.
• Cl? MnO4?? Mn2 Cl2

13
Problem

• HCl Al ? ?.

14
Problem

• Balance this reaction. Identify the oxidized
  element and oxidizing agent. Cu HNO3 ?
  Cu(NO3)2 NO2

15
Problem

• Balance this reaction. Identify the oxidized
  element and oxidizing agent.
• Cu H2SO4 ? CuSO4 SO2