In view of the signs of `Delta_(r)G^(0)` for the following reactions
`PbO_(2)+Pbrarr2PbO,Delta_(r)G^(0)lt0`
`SnO_(2)+Snrarr2SnO,Delta_(r)G^(0)gt0`
Which oxidation state are more characteristic for lead and tin?

Options

A. For lead `+4` and for tin `+2`
B. For lead `+2` and for tin `+2`
C. For lead `+4` and for tin `+4`
D. For lead `+2` and for tin `+4`

Answer

D

Explanation

`DeltaG^(@) lt 0` for `PbO_(2)+Pbtp2PbO`
`:.` Reaction is spontaneous in the forward direction
i.e., `Pb^(2+)` is more stable than `Pb^(4+)`
`DeltaG^(@) gt 0` for the reaction, `Sn^(+4)O_(2)+Snto2Sn^(2+)O`
`:.` Reaction is non-spontaneous in the forward direction but is spontaneous in the backward direction. Hence, `Sn^(4+)` will be more stable than `Sn^(2+)`