A volataic cell consists of an electode of solide silver immerse in a `0.10M AgNO_(3)` solution and an electrode of unknown metal `'X'` immersed in a `0.10M` solution `X(NO_(3))_(2)`. A porous barrier separates the two half of the cell. Also given `:`
`E^(c-)._((Ag^(o+)|Ag))=0.80V` and `E^(c-)._(cell)=1.05V` at `25^(@)C`
`X(s)|X^(2+)(1.0M)||Ag^(o+)(0.1M)|Ag(s)`
Which of the following statements regarding the cell and `X` is incorrect?

Options

A. Standard `EMF (E^(c-))` of `X^(2+)|X` is `-0.25V` at `25^(@)C`.
B. `X` is the stronger reducing agent than `H_(2)(g)`.
C. As the cell operates , the concentration of both `X^(2)` and `Ag^(o+)` increase in their respective half cells.
D. As the cell operates, the concentration of `X^(2+)` increases in the anode chamber while the concentration of `Ag^(o+)` decreases in the cathode chamber.

Answer

c

Explanation

`E^(c-)._(Ag^(o+)|Ag)=0.8V,E^(c-)._(X^(2)|X)=?,E^(c-)._(cell)=1.05V`
Now,` E^(c-)._(cell)=(E^(c-)._(Ag^(o+)|Ag)-E^(c-)._(X^(2)|X))`
`implies E^(c-)._(X^(2)|X)=-0.25V`
Since, `E^(c-)._(X^(2+)|X)ltE^(c-)._(H^(o+)|H2)`, X` is a stronger reducing agent than `H_(2)`.