Home
Class 12
CHEMISTRY
The standard redox potentials for the re...

The standard redox potentials for the reactions,
`MN^(2+) + 2e^(-)to Mn and Mn^(3+) + e^(-) are `-1.18V and 1.51V respectively. What is the redox potential for the reaction `Mn^(3+)+ 3e^(-) to Mn`?

Text Solution

Verified by Experts

The correct Answer is:
`-0.28`
`{:(Mn^(2+) + 2e^(-) to Mn, DeltaG_(1)=-nF E_(1)=-2 xx F xx (-1.18)),(Mn^(3+) + e^(-) to Mn^(2+), DeltaG_(2)=-nFE_(2)=-1 xx F xx (1.51)):}`
---------------------------------------------------------------------
Adding `Mn^(3+) + 3e^(-) to Mn, DeltaG_(3) =-3FE_(3)`
`DeltaG_(3) = DeltaG_(1) + DeltaG_(2)`
`-3FE_(3) =-2 xx F xx (-1.18) -(1) xx F xx (1.51)`
`E_(3) = -0.28 V`
Promotional Banner

Topper's Solved these Questions

  • CHAPTERWISE NUMERIC/INTEGER ANSWER QUESTIONS

    DISHA PUBLICATION|Exercise CHAPTER 23- COORDINATION COMPOUNDS|15 Videos

  • CHAPTERWISE NUMERIC/INTEGER ANSWER QUESTIONS

    DISHA PUBLICATION|Exercise CHAPTER 24- HALOALKANES AND HALOARENES|15 Videos

  • CHAPTERWISE NUMERIC/INTEGER ANSWER QUESTIONS

    DISHA PUBLICATION|Exercise CHAPTER-21: THE P-BLOCK ELEMENTS (GROUP 15,16,17 & 18)|15 Videos

  • BIOMOLECULES

    DISHA PUBLICATION|Exercise Exercise - 2 : Concept Applicator|30 Videos

  • CHEMICAL BONDING AND MOLECULAR STRUCTURE

    DISHA PUBLICATION|Exercise EXERCISE-2: CONCEPT APPLICATOR|30 Videos

Similar Questions

Explore conceptually related problems

E^(Theta) value for the couple Cr^(3+)//Cr^(2+) and Mn^(3+)//Mn^(2+) are -0.41 and +1.51 volts respectively. Considering these value select the correct option from the following statements.

In the reaction 3MnO_(2) + 4A1 to 3Mn + 2A1_(2) O_(3) the oxidizing agent is

E^(Theta) values for the couples Cr^(3+)//Cr^(2+) and Mn^(3+)//Mn^(2+) -0.41 and +1.51 volts respectively. Considering these values select the correct option from the following statements

Given the standard potential of the following at 25^(@)C . MnO_(2) rarr Mn^(3+), " "lE^(c-)=0.95V Mn^(3+) rarr Mn^(2+)," "E^(c-)=1.51V The standard potential of MnO_(2)rarr Mn^(2+) is

The electrode potential, E^(@) , for the reduction of MnO_(4)^(-)" to "Mn^(2+) in acidic medium is +1.51V . Which of the following metal(s) will be oxidised? The reduction reactions and standard electrode potentials for Zn^(2+), Ag^(+) and Au^(+) are given as Zn_((aq))^(2+)+2e^(-)rarrZn_((s)),E^(@)=-0.762V Ag_((aq))^(+)+e^(-)hArr Ag_((x)), E^(@)=+0.80V Au_((aq))^(+)+e^(-)hArr Au_((s)), E^(@)=+1.69V

Given below are the half -cell reactions Mn^(2+) + 2e^(-) rarr Mn, E^@ =- 1. 18 V 2 (Mn^(3+) = E^(-) rarr Mn^(2+)). E^@ = + 1.5 V The E^@ for Mn^(2+) rarr Mn+ 2 Mn^(3+) will be.

The standard oxidation potentials for Mn^(3+) ion acid solution are Mn^(2+)overset(-1.5V)toMn^(3+)overset(-1.0V)toMnO_(2) . Is the reaction 2Mn^(3+)+2H_(2)OtoMn^(2+)+MnO_(2)+4H^(+) spontaneous under conditions of unit activity? What is the change in free energy?

The standard oxidation potential for Mn^(3+) ion acid solution are Mn^(2+)overset(-1.5V)rarrMn^(3+) overset(-1.0V)rarr MnO_(2) . Is the reaction 2Mn^(3+)+2H_(2)O rarr Mn^(2+)+MnO_(2)+4H^(+) spontaneous under conditions of unit activity ? What is the change in free energy ?