Home
Class 12
CHEMISTRY
Assertion (A): For four half- cell react...

Assertion `(A):` For four half`-` cell reactions involving different number of electrons,
`E_(4)=E_(1)+E_(2)+E_(3)`
Reaction `(R): DeltaG_(4)=DeltaG_(1)+DeltaG_(2)+DeltaG_(3)`

A

If both `(A)` and `(R)` are correct, and `(R)` is the correct explanation of `(A)`.

B

If both `(A)` and `(R)` are correct, but `(R)` is not the correct explanation of `(A)`.

C

If `(A)` is correct, but `(R)` is incorrect.

D

If `(A)` is incorrect, `(R)` is correct.

Text Solution

Verified by Experts

The correct Answer is:
D
`(A)` is incorrect since `EMFs` are neither additive nor subtractice.
`(R)` is correct but not the explanation of `(A)`. `(R)` is an independent statement and `DeltaG` are additive or subtrative.
Promotional Banner

Topper's Solved these Questions

  • ELECTROCHEMISTRY

    CENGAGE CHEMISTRY|Exercise Exerciseinterger|8 Videos

  • ELECTROCHEMISTRY

    CENGAGE CHEMISTRY|Exercise Exercisefill In The Blanks|25 Videos

  • ELECTROCHEMISTRY

    CENGAGE CHEMISTRY|Exercise Exercises Ingle Correct|178 Videos

  • D AND F BLOCK ELEMENTS

    CENGAGE CHEMISTRY|Exercise Archives Subjective|29 Videos

  • GENERAL PRINCIPLES AND PROCESS OF ISOLATION OF ELEMENTS

    CENGAGE CHEMISTRY|Exercise Archives (Subjective)|14 Videos

Similar Questions

Explore conceptually related problems

Statement : If two half reaction with electrode potential E_(1)^(@) and E_(2)^(@) gives a third reaction then, DeltaG_(3)^(@) = DeltaG_(1)^(@) + DeltaG_(2)^(@) Explanation : E_(3)^(@) = E_(1)^(@) + E_(2)^(@)

Read the following passage for the evaluation of E^(@) when different number of electrons are involved. Consider addition of the following half reactions (1) Fe^(3+)(aq)+3e^(-)rarr Fe(s) E_(1)^(@)=0.45V (2) Fe(s)rarr Fe^(2+)(aq)+2e^(-) E_(2)^(@)=-0.04V (3) Fe^(3+)(aq)+e^(-)rarr Fe^(2+)(aq) E_(3)^(@)= ? Because half-reactions (1) and (2) contains a different number of electrons, the net reaction (3) is another half-reaction and E_(3)^(@) can't be obtained simply by adding E_(1)^(@) and E_(3)^(@) . The free - energy changes however, are additive because G is a state function : Delta G_(3)^(@)=Delta G_(1)^(@)+Delta G_(2)^(@) Standard electrode potential for the half-cell Fe^(3+)//Fe^(2+) of the reaction (3) is :

Read the following passage for the evaluation of E^(@) when different number of electrons are involved. Consider addition of the following half reactions (1) Fe^(3+)(aq)+3e^(-)rarr Fe(s) E_(1)^(@)=0.45V (2) Fe(s)rarr Fe^(2+)(aq)+2e^(-) E_(2)^(@)=-0.04V (3) Fe^(3+)(aq)+e^(-)rarr Fe^(2+)(aq) E_(3)^(@)= ? Because half-reactions (1) and (2) contains a different number of electrons, the net reaction (3) is another half-reaction and E_(3)^(@) can't be obtained simply by adding E_(1)^(@) and E_(3)^(@) . The free - energy changes however, are additive because G is a state function : Delta G_(3)^(@)=Delta G_(1)^(@)+Delta G_(2)^(@) If number of electrons in the reacton are n_(1),n_(2) and n_(2) respectively, then standard electrode potential of reation (3) is

Read the following passage for the evaluation of E^(@) when different number of electrons are involved. Consider addition of the following half reactions (1) Fe^(3+)(aq)+3e^(-)rarr Fe(s) E_(1)^(@)=0.45V (2) Fe(s)rarr Fe^(2+)(aq)+2e^(-) E_(2)^(@)=-0.04V (3) Fe^(3+)(aq)+e^(-)rarr Fe^(2+)(aq) E_(3)^(@)= ? Because half-reactions (1) and (2) contains a different number of electrons, the net reaction (3) is another half-reaction and E_(3)^(@) can't be obtained simply by adding E_(1)^(@) and E_(3)^(@) . The free - energy changes however, are additive because G is a state function : Delta G_(3)^(@)=Delta G_(1)^(@)+Delta G_(2)^(@) For the reactions (1) MnO_(4)^(-)+8H^(+)+5e^(-)rarr Mn^(2)+4H_(2)O E^(@)=1.51 V (2) MnO_(2)+4H^(+)+2e^(-)rarr Mn^(2+)2H_(2)O E^(@)=1.32 then for the reaction (3) MnO_(4)^(-)+4H^(+)+3e^(-)rarrMnO_(2)+2H_(2)O, E^(@) is

Consider the following equations for a cell reaction, A + B rarr C + D , E^(@) = x "volt", Delta G= Delta G_(1) 2A + 2B rarr 2C + 2D, E^(@) = y "volt", DeltaG = DeltaG_(2) Then,

If the DeltaG^(@) of a cell reaction AgCI+e^(-) is -21.20KJ standard emf of cell is

In an electrochemical cell, if E^(@) is the e.m.f. of the cell involving 'n' mole of electrons, then DeltaG^(@) is

Assertion (A): There is no reaction known for which DeltaG is positive, yet it is spontaneous. Reason (R ) : For photochemical reaction, DeltaG is negative.

CENGAGE CHEMISTRY-ELECTROCHEMISTRY-Exerciseassertion -Reasoning
  1. Assertion (A): A saturated solution of KCl is used in making salt brid...

    Text Solution

    |

  2. Assertion (A): When an aqueous solution of KNO(3) is electrolyzed, pot...

    Text Solution

    |

  3. Assertion (A): For four half- cell reactions involving different numbe...

    Text Solution

    |

  4. Assertion (A): 1 Faraday of electricity deposits 1 g equivalent of Ag ...

    Text Solution

    |

  5. Assertion (A): The mobility of Na^(o+) is lower than that of K^(o+) io...

    Text Solution

    |

  6. Assertion (A): Equivalent conductance increase with dilution for an el...

    Text Solution

    |

  7. Assertion (A): wedge(m(H^(o+))) and wedge(m(overset(c)(O)H)) ions are ...

    Text Solution

    |

  8. Assertion (A): Ionic conductivities increase with increase of temperat...

    Text Solution

    |

  9. Assertion (A: Cell constant is the EMF of a cell. Reason (R): Cell c...

    Text Solution

    |

  10. Assertion (A): At the end of electrolysis using Pt electrodes, an aque...

    Text Solution

    |

  11. Assertion (A): Cu liberates H(2)(g) from a dilute solution of HCl. R...

    Text Solution

    |

  12. Assertion(A): Na^(o+) ions are discharged in preference to H^(o+) ions...

    Text Solution

    |

  13. Assertion (A) : Cu gets readily corroded in acidic aqueous solution. ...

    Text Solution

    |

  14. Assertion (A) : Galvanized iron does not rust. Reason (R): Zn has a...

    Text Solution

    |

  15. Assertion (A): For a Daniell cell : Zn|Zn^(2+)||Cu^(2+)|Cu with E(ce...

    Text Solution

    |

  16. Assertion (A): The electrolysis of NaCl solution gives H(2)(g) at cath...

    Text Solution

    |

  17. Assertion (A) : Fe is protected from corrosing by connecting Mg metal ...

    Text Solution

    |

  18. Assertion (A) : The Daniell cell becomes dead after sometimes. Reaso...

    Text Solution

    |

  19. Assertion (A): wedge^(@).(eq(CH(3)COOH)) cannote be determines experim...

    Text Solution

    |

  20. Assertion (A) : The presence of CO(2) in the air accelerates corrosio...

    Text Solution

    |