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Question
The two half-reactions that are used in the direct methanol fuel cell are shown below.
I 2 CH3OH(aq) + 2 H2O(l) -> 2 CO2(g) + 12 H+(aq) + 12 e"
II 3 O2(g) + 12 H+(aq) + 12 e- -> 6 H2O(l)
The electrode at which half-reaction I occurs is the ________ at which ________ is oxidized, and half-reaction II occurs at the ________ at which ________ is reduced.
Answer
This answer is hidden. It contains 22 characters.
Related questions
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B) covalent and basic
C) ionic and acidic
D) ionic and basic
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Picture (a) shows p-orbital overlap between carbon and oxygen atoms; picture (b) shows p-orbital overlap between silicon and oxygen atoms. Based on these pictures, it is expected that
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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.
C) carbon and oxygen form better π bonds than silicon and oxygen, so C=O double bonds are stronger than Si=O double bonds.
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Q:
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B) element B
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When 3.600 grams of anhydrous magnesium chloride were exposed to moist air, water was absorbed by the sample. If the resulting hydrated compound has a mass of 4.962 grams, what is the chemical formula of the hydrate?
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Q:
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Q:
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Q:
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Q:
Covalent hydrides of the type MH3 are likely to form with elements of what group?
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Q:
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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:
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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B) magnesium is more easily oxidized than iron.
C) magnesium is inert.
D) magnesium and steel form a corrosion resistant alloy.
Q:
Which of the following statements concerning the rusting of iron is false?
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B) The metal is reduced.
C) The rusting of iron requires both oxygen and water.
D) Salt increases the rate of corrosion by providing ions to carry the current.
Q:
Shown below are the reactions occurring in the direct methanol fuel cell (DMFC).I 2 CH3OH(aq) + 2 H2O(l) -> 2 CO2(g) +12 H+(aq) +12 e-II 3 O2(g) + 12 H+(aq) + 12 e- -> 6 H2O(l)Overall 2 CH3OH(aq) + 3 O2(g) -> 2 CO2(g) + 4 H2O(l)Which is the anode reaction, and what is being oxidized in the overall reaction?A) I, CH3OHB) I, H2OC) II, O2D) II, H+