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You've already seen many redox reactions in this book; we just didn't call them that. You've been memorizing them so far, but now you can just balance them on the fly. Try your hand at these classics:
A: C6H10O5 + 6 O2 = 6 CO2 + 5 H2O
Cellulose is the reductant and oxygen is the oxidant.
A: 2 CuCO3 + C = Cu + 3 CO2
Copper carbonate is the oxidizing agent and charcoal is the reducing agent.
A: 2 PbS + 3 O2 = 2 PbO + 2 SO2
Lead sulfide is the reducing agent and oxygen is the oxidizing agent.
A: 6 CO2 + 6 H2O = C6H12O6 + 6 O2
I know that these were pretty simple reactions, as redox reactions go, and human nature being what it is, you may have figured them out without using the sidebar Redox in a Nutshell. If you did, you wasted the easy exercises which were intended to give you some practice with the method without freaking you out. The reactions are going to get harder, not because I'm going to make it harder, but because Nature doesn't always make it easy. And without the method, how are you going to know which is the oxidant and which is the reductant in a reaction like the third example? So go back and do them again if you need to, and then try out these harder problems:
A: 10 KMnO4 + 4 C2H4(OH)2 = 3 CO2 + 5 Mn2O3 + 5 K2CO3 + 12 H2O
Potassium permanganate is the oxidant and ethylene glycol is the reductant.
A: 42 KMnO4+12 C3H5(OH)3 = 15 CO2+21 Mn2O3+21 K2CO3+48 H2O
Potassium permanganate is the oxidant and glycerol is the reductant.
A: 3 Cu + 8 HNO3 = 2 NO + 3 Cu(NO3)2 + 4 H2O
Nitric acid is the oxidant and copper is the reductant. Hint: nitric acid appears in both half-reactions.
A: C8H18 + 25 NH4NO3 = 25 N2 + 8 CO2 + 59 H2O
Ammonium nitrate is the oxidant and octane is the reductant. This reaction is responsible for one kind of "fertilizer bomb."
A: 5 S + 6 KNO3 + 2 H2O = 2 H2SO4 + 3 N2 + 3 K2SO4
Sulfur is the reductant and potassium nitrate is the oxidant. Hint: sulfur appears in both half-reactions.
A: 2 Al + 6 H2O = 2 Al(OH)3 + 3 H2
Aluminum is the reductant and water is the oxidant. This reaction is quite vigorous in alkaline solutions, which is why we avoided using an aluminum pot for making potash.
When you can solve these problems without consulting the sidebar Redox in a Nutshell, you will be prepared to balance any redox equation in this book. Your notebook for this project may omit the "Observations" section, as no manipulation of materials is involved in this project, but you should summarize the chronic and acute toxicities of either mercury, silica, or asbestos.