Standard free energies of formation (I `kJ //`mol ) at `298 K` are ` -237 .2 , - 394 .4` and `- 8.2 ` for `H_2 O(1), CO_2 (g)` and pentange (g) , respectively . The value of `E_(cell)^@` for the pentane-oxygen fuel cell is .A. `1.968V`B. `2.0968V`C. 1.0968VD. 0.0968V

Standard free energies of formation (I `kJ //`mol ) at `298 K` are ` -

1.	Standard free energies of formation (I `kJ //`mol ) at `298 K` are ` -237 .2 , - 394 .4` and `- 8.2 ` for `H_2 O(1), CO_2 (g)` and pentange (g) , respectively . The value of `E_(cell)^@` for the pentane-oxygen fuel cell is .A. `1.968V`B. `2.0968V`C. 1.0968VD. 0.0968V
Answer» Correct Answer - C The balanced equation for the pentane oxygen cell reaction will be `C_(5)H_(12)+8O_(2)rarr5CO_(2)+6H_(2)O,n=32` `(because 16O+32e^(-)rarr16O^(2-))` `DeltaG=5xxDelta_(f)G^(@)(CO_(2))+6 xxDelta _(f)G^(@)(H_(2)O)` `-Delta_(f)G^(@)(C_(5)H_(12))+8xxDelta_(f)G^(@)(O_(2))` `= 5xx(-394.4)+6(-237.2)-(-8.2)-0` `=-1972-1423.2+8.2` `=-3387 kJ "mol"^(-1)` `DeltaG_(f)=-nFE_("cell")^(@)` `therefore -3387000=-32xx96500xxE_("cell")^(@)` or `E_("cell")^(@)=1.0968V`

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Standard free energies of formation (I `kJ //`mol ) at `298 K` are ` -237 .2 , - 394 .4` and `- 8.2 ` for `H_2 O(1), CO_2 (g)` and pentange (g) , respectively . The value of `E_(cell)^@` for the pentane-oxygen fuel cell is .A. `1.968V`B. `2.0968V`C. 1.0968VD. 0.0968V

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