For hydrogen oxygen fuel cell with reaction `2H_(2)(g)+O_(2)(g) rarr 2 H_(2)O(l)` `DeltaG_(f)^(c-)(H_(2)O)=-237.2kJ mol^(-1)`. Hence, `EMF` of the fuel cell isA. `+2.46 V`B. `-2.46V`C. `+1.23 V`D. `-1.23V`

For hydrogen oxygen fuel cell with reaction `2H_(2)(g)+O_(2)(g) rarr 2

1.	For hydrogen oxygen fuel cell with reaction `2H_(2)(g)+O_(2)(g) rarr 2 H_(2)O(l)` `DeltaG_(f)^(c-)(H_(2)O)=-237.2kJ mol^(-1)`. Hence, `EMF` of the fuel cell isA. `+2.46 V`B. `-2.46V`C. `+1.23 V`D. `-1.23V`
Answer» Correct Answer - c Fuel cell reaction is `:` `2H_(2)(g)+O_(2)(g) rarr 2H_(2)O(l)` At anode `: 2H_(2)(g)+4overset(c-)(O)H(aq) rarr 4H_(2)O+4e^(-)` `(` Half oxidation `)` At cathode `:` `O_(2)(g)+2H_(2)O(l)+4e^(-)rarr 4 overset(c-)(O)H(aq)` `(` Half reduction `)` `ulbar(Cell reaction : 2H_(2)(g)+O_(2)(g)rarr2H_(2)O(l))` `:. n_(cell)=4` `Delta_(r)G^(c-)=2Delta_(f)G^(c-)._((H_(2)o))-2Delta_(f)G^(c-)._((H_(2)O))-2Delta_(f)G^(c-)._((O_(2)))` `=2(-237.2)kJ mol^(-1)-2xx0-0` `=2(-237.2k J mol^(-1)` `Delta_(r)G^(c-)=-nFE^(c-)._(cell)` `2(-237.2)kJ mol^(-1)=-4xx96500CxxE^(c-)._(cell)` `:. E^(c-)._(cell)=1.23V`

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For hydrogen oxygen fuel cell with reaction `2H_(2)(g)+O_(2)(g) rarr 2 H_(2)O(l)` `DeltaG_(f)^(c-)(H_(2)O)=-237.2kJ mol^(-1)`. Hence, `EMF` of the fuel cell isA. `+2.46 V`B. `-2.46V`C. `+1.23 V`D. `-1.23V`

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