What type of a battery is lead storage battery? Write the anode and cathode reactions and the overall cell reaction occurring in the operation of a lead storage battery.
(b) Calucluate the potential for half-cell containing.
0.10 M `K_(2)Cr_(2)O_(7)(aq), 0.20 M Cr^(3+) (aq) and 1.0 xx 10^(-4) M H^(+) (aq)`
The half -cell reaction is
`Cr_(2)O_(7)^(2-) (aq) + 4H^(+) (aq) + 6 e^(-) to 2 Cr^(3+) (aq) + 7H_(2)O(l)`
and the standard electron potential is given as `E^(o) = 1.33V`.

Explanation

`E_(cell) = E_(cell)^(@) - (0.0591)/(n) "log" ([Cr^(3+)]^(2))/([Cr_(2) O_(7)^(2-)][H^(+)]^(14))`
`E_(cell)^(@) = 1.33 V , [Cr^(3+)] = 0.20 M`
`Cr_(2) O_(7)^(2-) ] = 0.1 M , [H^(+)] = 1.0 xx 10^-4 M , n = 6`
`therefore E_(cell) = 1.33 - (0.0591)/(6) "log" ((0.20)^(3))/((0.10) (10^(-4))^(14))`
`= 1.33 - (0.0591)/(6) log 0.4 xx 10^(56)`
`= 1.33 - (0.0591)/(6) xx 55.60`
`= 1.33 - 0.55 = 0.78` V