A hypothetical elecrochemical cell is shown below:
`A^(ɵ)|A^(+)(xM)||B^(+)(yM)||B^(o+)`
The emf measured is `+0.20 V`. The cell reaction is

Options

A. `A+B^(+) to A^(+)+B`
B. `A^(+)+B to A+B^(+)`
C. `A^(+)+e^(-) to A, B^(+) +e^(-) to B`
D. the cell reaction cannot be predicted

Answer

A

Explanation

(a) Electrochemical cell,
`A|A^(+) (xM)||B^(+)(yM)|B`
EMF of cell is +0.20 V. So, cell reaction is possible. The half-cell reactions are given as follows
(i) At negative pole
`A to A^(+) +e^(-) " (oxidation)"`
(ii) At positive pole
`B^(+)+e^(-) to B " (reduction)"`
Hence, cell reaction is
`A+B^(+) to A^(+) +B, E_(cell)^(@)=+0.20 V`