Determine range of `E^(@)` values for this reaction `X_(aq)^(2+)+2e^(-)toX(s)` for given conditions:
(a). If the metal X dissolve in `HNO_(3)` but not in `HCl` it can displace `Ag^(+)` ion but not `Cu^(2+)` ion.
(b). If te metal X is HCl acid producing `H_(2)(g)` but does not displace either `Zn^(2+)` or `Fe^(2+)`
Given `E_(Ag^(+)//Ag)^(0)=0.8V" "E_(Fe^(2+)//Fe)^(0)=-0.44`
`E_(Cu^(2+)//Cu)^(0)=0.34V" "E_(NO_(3)^(-)//NO)^(0)=0.96V" "E_(zn^(2+)//Zn)^(0)=-0.76V`

Answer

(a). `0.34ltE^(@)lt0.8`
(b). `-0.44ltE^(@)lt0`

Explanation

(a). Metal should below hydrogen and `Cu^(2_)` but should above `Ag^(+)` in series.
(b). Metal should above hydrogen but should below from `Zn^(2+)` and `Fe^(2+)` both.