Question

For the electrochemicl cell, `M|M^(+)||X^(-)|X E_((M^(+)//M))^(@) = 0.44 V` and `E_((X//X^(-)))^(@) = 0.33 V`
From this data one can deduce that :
A. `M + X rarr M^(+) + X^(-)` is the spontaneous reaction
B. `M^(+) + X^(-) rarr M + X` is the spontaneous reaction
C. `E_(cell) = 0.77 V`
D. `E_(cell) = -0.77 V`

Answer 1

Correct Answer - B
`E_(cell) = E_(OP_(M//M^(+)))^(@) + E_(RP_(X//X^(-)))^(@)`
`= -0.44 + 0.33 = -0.11 V` for
`M + X rarr M^(+) + X^(-)`. Thus reaction is non-spontaneous. The spontaneous reaction in `M^(+) + X^(-) rarr M + X, E^(@) = 0.11 V`