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Question
Shown below are the reactions occurring in the proton-exchange membrane (PEM) fuel cell.
I 2 H2(g) -> 4 H+(aq) + 4 e-
II O2(g) + 4 H+(aq) + 4 e- -> 2 H2O(l)
Overall 2 H2(g) + O2(g) -> 2 H2O(l)
Which is the cathode reaction, and what is being oxidized in the overall reaction?
A) I, H2
B) I, O2
C) II, H2
D) II, O2
Answer
This answer is hidden. It contains 1 characters.
Related questions
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In the following picture of an oxide, darkly-shaded spheres represent oxygen atoms or ions and lightly-shaded spheres represent atoms or ions of a third-row element in its highest oxidation state. Tell whether the oxide is covalent or ionic and whether the oxide is acidic or basic. A) covalent and acidic
B) covalent and basic
C) ionic and acidic
D) ionic and basic
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B) silicon and oxygen form better σ bonds than carbon and oxygen, so Si-O single bonds are stronger than C-O single bonds.
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Q:
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Q:
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Covalent hydrides of the type MH3 are likely to form with elements of what group?
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Q:
The bright colors of anodized titanium are due toA) electrodeposition of organic dyes on the titanium surface.B) the formation of a titanium alloy with chromium and copper.C) iridescence involving the semitransparent outer layer of TiO2.D) trapping of organic dye molecules in a spongy TiO2 matrix.
Q:
Chromium can be electroplated from an aqueous solution containing sulfuric acid and chromic acid, H2CrO4. What current is required to deposit chromium at a rate of 1.25 g/min?
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How many grams of chromium metal are plated out when a constant current of 8.00 A is passed through an aqueous solution containing Cr3+ ions for 40.0 minutes?
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Q:
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Q:
O2(g) + 4 H+(aq) + 4 e--> 2 H2O(l) E = +1.23 VI2(s) + 2 e- -> 2 I-(aq) E = +0.54 V2 H2O(l) + 2 e- -> H2(g) + 2 OH-(aq) E = -0.83 VMg2+(aq) + 2 e- -> Mg(s) E = -2.37 VBased on the data above, electrolysis of an aqueous solution of MgI2, with inert electrodes, is expected to produceA) Mg at the cathode and I2 at the anode.B) H2 at the cathode and I2 at the anode.C) Mg at the cathode and O2 at the anode.D) H2 at the cathode and O2 at the anode.
Q:
A steel pipe can be protected from corrosion by attaching the pipe to a piece of magnesium because
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Q:
Which of the following statements concerning the rusting of iron is false?
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Q:
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