1. Applications of Redox Electrochemistry

2. Review Oxidation reduction reactions involve a transfer of electrons. OIL-RIG Oxidation Involves Loss Reduction Involves Gain LEO-GER Lose Electrons Oxidation Gain Electrons Reduction

3. Solid lead(II) sulfide reacts with oxygen in the air at high temperatures to form lead (II) oxide and sulfur dioxide. Which substance is a reluctant (reducing agent) and which is an oxidant (oxidizing agent)? A. PbS, reductant; O 2, oxidant B. PbS, reductant; SO 2, oxidant C. Pb 2+, reductant; S 2-, oxidant D. PbS, reductant; no oxidant E. PbS, oxidant; SO 2, reductant

4. Balancing Redox Reactions by ½ Reactions –Acidic Potassium dichromate is a bright orange compound that can be reduced to a blue-violet solution of Cr 3+ ions. Under certain conditions, potassium dichromate reacts with ethyl alcohol as follows: H + (aq) + Cr 2 O 7 2- (aq) + C 2 H 5 OH (l) ↔Cr 3+ (aq) + CO 2 (g) + H 2 O(l) Balance this equation using the ½ reaction method.

5. Balancing Redox Reactions by ½ Reactions- (Basic) Silver is sometimes found in nature as large nuggets; more often it is found mixed with other meals and their ores. An aqueous solution containing cyanide ion is often used to extract the silver using the following reaction that occurs in basic solution. Ag(s) + CN - (aq) + O 2 (g) ↔ Ag(CN) 2 - (aq) Balance the equation using the ½ reaction method.

6. Applications Moving electrons is electric current 8H + + MnO 4 + 5Fe 2+ + 5e - → Mn +2 + 5Fe +3 + 4H 2 O