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UNIT 5 Fuel cells confusion methanol - oxygen and ethanol - oxygen fuel cells

1. In a methanol - oxygen fuel cell, methanol is oxidized at the anode.
2. In a ethanol - oxygen fuel cell, ethanol is oxidized at the cathode.

Exactly what factor determines the location on where these fuels get oxidized?


I got confused about the anodes and cathodes in a fuel cell.

In an electrochemical cell ie fuel cell,
Anode is negative
Cathode is negative

Whereas in electrolytic cells
Anode is positive
Cathode is positive

<fuel> gets oxidized at the anode, oxygen gets reduced at the cathode.
(edited 6 years ago)
There must be some mistake as both ethanol and methanol get oxidised at the anode.Oxidation happens always at the anode and reduction at the cathode in the fuel cells.This is what i know,if am mistaken pls someone correct me
Original post by GeorgeDoofer13
There must be some mistake as both ethanol and methanol get oxidised at the anode.Oxidation happens always at the anode and reduction at the cathode in the fuel cells.This is what i know,if am mistaken pls someone correct me


There is also this question :
In a hydrogen - oxygen fuel cell, hydrogen is oxidized at the anode AND oxygen is reduced at the anode.
Question paper, question 5
http://pmt.physicsandmathstutor.com/download/Chemistry/A-level/Past-Papers/Edexcel-IAL/Unit-5/June%202015%20(IAL)%20QP%20-%20Unit%205%20Edexcel%20Chemistry%20A-level.pdf
Mark scheme
http://pmt.physicsandmathstutor.com/download/Chemistry/A-level/Past-Papers/Edexcel-IAL/Unit-5/June%202015%20(IAL)%20MS%20-%20Unit%205%20Edexcel%20Chemistry%20A-level.pdf


The following happens:
Anode: H2-> 2H+ and 2electrons thus oxidation
Cathode: O2-> H20 which the half equation is O2+ 4H+ 4 electrons-> 2 H2O

Hydrogen goes from 0 to +1 oxidised
Oxygen from 0 to -2 reduced thus cathode reduction positive electrode

Remember this:
oxidation anode negatice electrode
reduction cathode positive electrode
(edited 6 years ago)

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