A fuel cell involves combustion of butane at at 1 atm and 298 K `underset((g))(C_4H_(10))+underset((g))(13/2O_2)rarrunderset((g))(4CO_2)+underset((l))(5H_2O)`
`DeltaG^@=-2746"kJ//mol"` The value of `E_("cell")^@` is nearly ?

Options

A. 0.545 V
B. 1.09 V
C. 0.922 V
D. 0.755 V

Answer

B

Explanation

`overset(-10)(C_(4))overset(+10)(H_(10))(g)+(13)/(2)O_(2)(g)to4overset(+4)(C)overset(-4)(O_(2))+5H_(2)O(l)`
Change in oxidation number of carbon
`=4(+4)-(-10)=26`
or `(13)/(2)O_(2)^(@)+26e^(-)to13O^(2-)`
`(8O^(2-)` in `4CO_(2)` and `5O^(2-)` in `5H_(2)O)`
Thus, cell reaction involves 26 electrons, i.e.,
n=26
`E_(cell)^(@)=(DeltaG^(@))/(nF)=(-(-2746)xx1000)/(26xx96500)=+1.09V`