Which of the following cell reactions correctly represent the electrolysis of water?
Correct answer: D. 2H2O -> O2(g) +4H+ + 4e
- A. 2H+ + 2e -->H2(g)
- B. 2H2O +2e -> H2(g)+2(OH-)
- C. 2(OH-) -> 2H2O + O2(g) +4e
- D. 2H2O -> O2(g) +4H+ + 4e
Explanation
Here's a breakdown of the electrolysis of water:Cathode: Water is reduced to hydrogen gas. 2H+ + 2e- -> H2(g) Anode: Water is oxidized to oxygen gas. 2H2O -> O2(g) + 4H+ + 4e- The overall reaction is the sum of these two half-reactions:2H2O -> 2H2(g) + O2(g)Therefore, the correct answer is d, which represents the overall reaction at the anode.
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