Standard free energies of formation in kJ/mol) at 298 K are -237.2, -394.4 and -8.2 for `H_(2)O(l),CO_(2)(g)` and pentane (g) respectively. The value of `E_(cell)^(@)` for the pentane-oxygen fuel cell isA. 1.968 VB. 2.0968VC. 1.0968VD. 0.0968V

Standard free energies of formation in kJ/mol) at 298 K are -237.2, -3

1.	Standard free energies of formation in kJ/mol) at 298 K are -237.2, -394.4 and -8.2 for `H_(2)O(l),CO_(2)(g)` and pentane (g) respectively. The value of `E_(cell)^(@)` for the pentane-oxygen fuel cell isA. 1.968 VB. 2.0968VC. 1.0968VD. 0.0968V
Answer» Correct Answer - C The balanced equation for pentane-oxygen cell reaction will be `C_(5)H_(12)+8O_(2)to5CO_(2)+6H_(2)O,n=32` `Delta_(r)G^(@)=[5xxDelta_(f)G^(@)(CO_(2))+6Delta_(f)G^(@)(H_(2)O)]-[Delta_(f)G^(@)(C_(5)H_(12))+8Delta_(f)G^(@)(O_(2))]` `=[5(-394.5)+6(-237.2)]-[(-8.2)+0]` `=-1972-1423.2+8.2=-3387" kJ "mol^(-1)` `Delta_(f)G^(@)=-nFE_(ceLL)^(@)` `therefore-3387000=-32xx96500xxE_(cell)^(@)` or `E_(cell)^(@)=1.0968V`

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Standard free energies of formation in kJ/mol) at 298 K are -237.2, -394.4 and -8.2 for `H_(2)O(l),CO_(2)(g)` and pentane (g) respectively. The value of `E_(cell)^(@)` for the pentane-oxygen fuel cell isA. 1.968 VB. 2.0968VC. 1.0968VD. 0.0968V

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