Home
Class 12
CHEMISTRY
Two electrochemical cells, Zn^(2+)|Zn^(2...

Two electrochemical cells, `Zn^(2+)|Zn^(2+)||Cu^(2+)|Cu` and `Fe|Fe^(2+)||Cu^(2+)|Cu` are connected in series. What will be the net e.m.f. of the cell at `25^(@)C` ?
Given : `E^(@)` of `Zn^(2+)|Zn=-0.76" V"`,
`Cu^(2+)|Cu=+0.34" V",Fe^(2+)|Fe=-0.41" V"`

A

`+1.85" V"`

B

`-1.85" V"`

C

`+0.83" V"`

D

`-0.83" V"`

Text Solution

Verified by Experts

The correct Answer is:
A
(a) emf of the cell,`Zn(s)|Zn^(2+)(aq)||Cu^(2+)(aq)|Cu(s)` is :
`E_(Cu^(2+)//Cu)^(@)-E_(Zn^(2+)//Zn)^(@)=+0.34-(-0.76)=1.10" V"`
emf of the cell, `Fe(s)|Fe^(2+)(aq)||Cu^(2+)(aq)|Cu(s)` is :
`E_(Cu^(2+)//Cu)^(@)-E_(Fe^(2+)//Fe)^(@)=+0.34-(0.41)=0.75" V"`
Since the two electrodes are connected in series, the net emf of cell is :
`=1.10+0.75=+1.85" V"`
Promotional Banner

Topper's Solved these Questions

  • ALCOHOLS AND PHENOLS

    DINESH PUBLICATION|Exercise COMPLETION QUESTION|2 Videos

  • ALCOHOLS AND PHENOLS

    DINESH PUBLICATION|Exercise NCERT In-Text Questions|9 Videos

  • ALDEHYDES AND KETONES

    DINESH PUBLICATION|Exercise Interger|5 Videos

Similar Questions

Explore conceptually related problems

In the cell, Zn|Zn^(2+)"||"Cu^(2+)|Cu ________.

The e.m.f of the cell Zn|Zn^(2)||Cu^(2+)|Cu can be increased by

Calculate the maximum work that can be obtained from the decimolar Daniell cell at 25^(@)C . Given E^(c-)._((Zn^(2+)|Zn))=-0.76V and E^(c-)._((Cu^(2+)|Cu))=0.34V

For a standard cell Zn(s)|Zn^(2+)(1 M)||Cu^(2+)(1 M)|Cu(s) Write the electrode reaction and cell reaction. Also find the e.m.f. of cell if ? E_(Zn^(2+)|Zn)^(@)=-0.76" V", E_(Cu^(2+)|Cu)^(@)=+0.34" V" .

Can 1 M ZnSO_(4) be stored in a vessel made up of copper ? Given : E_(Zn^(2+)//Zn)^(@)=-0.76 " and "E_(Cu^(2+)//Cu)^(@)=+0.34" V" ?