Answer
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Work Step by Step
The species oxidized shows an increase in oxidation states and is called the reducing agent.
The species reduced shows a decrease in oxidation states and is called the oxidizing agent.
The pertinent oxidation states are listed by the substance oxidized and the substance reduced.
a) Is Redox, Oxidizing agent = H2O , Reducing agent = CH4 , Substance oxidized C (C, −4 → +2), Substance reduced H (H, +1 → 0)
b) Is Redox, Oxidizing agent = Ag+, Reducing agent = Cu , Substance oxidized = Cu (0 → +2), Substance reduced Ag+ (Ag, +1 → 0)
c) Is Redox, Oxidizing agent = H+, Reducing agent = Zn , Substance oxidized = Zn (0 → +2) , Substance reduced = H+ (H, +1 → 0)
d) It NOT redox, there is no change in any of the oxidation numbers
