A direct methanol fuel cell has the overall reaction CH3OH + 3/2 O2 -> CO2 + 2H2O. Which statements are correct?

Six moles of electrons pass through the external circuit per mole of methanol consumed

Oxygen is reduced at the cathode

Methanol is oxidised to CO2 at the anode

Six moles of electrons pass through the external circuit per mole of methanol consumed

Oxygen is reduced at the cathode

Three moles of O2 are consumed per mole of methanol

Methanol is oxidised to CO2 at the anode

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JEE Main levelOne or more correct optionsDifficulty 2 of 3ec161

A direct methanol fuel cell has the overall reaction $CH X_{3} OH + \frac{3}{2} O X_{2} CO X_{2} + 2 H X_{2} O$ . Which statements are correct?

ASix moles of electrons pass through the external circuit per mole of methanol consumed
BOxygen is reduced at the cathode
CThree moles of $O X_{2}$ are consumed per mole of methanol
DMethanol is oxidised to $CO X_{2}$ at the anode

Answer: A, B, D

Carbon goes from

- 2

CH X_{3} OH

+ 4

CO X_{2}

, a loss of

6

electrons per molecule, so (A) is correct; this is the anodic oxidation, so (D) is correct. These electrons reduce oxygen at the cathode, (B) correct. Six electrons reduce

6/4 = 1.5 mol

O X_{2}

, matching the balanced equation, so (C) is wrong.

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A direct methanol fuel cell has the overall reaction CHX3​OH+23​OX2​​COX2​+2HX2​O. Which statements are correct?

Answer: A, B, D

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A direct methanol fuel cell has the overall reaction $CH X_{3} OH + \frac{3}{2} O X_{2} CO X_{2} + 2 H X_{2} O$ . Which statements are correct?