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Question #44900
The Question
An electrochemical cell operates at in an inert molten fluorocarbon solvent. The cathode compartment contains a mixture of solid and , while the anode is a standard fluorine gas electrode (, ). \ \ Given the following standard thermodynamic data at :\ \ \ \ \ \ \ \ \ \ Calculate the standard reduction potential () for the half-cell reaction: \ \ \ (Assume Faraday's constant )
Options
- A.
- B.
- C.
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Mechanism_Trap
Don't get tricked by the process! Learn the mechanical traps used in competitive exam questions.
Concepts Behind This Question
Stability of High O.S. Fluorides/Oxides|Gibbs Energy and Spontaneity|Electrolysis Product Prediction
Why This Question Is Tricky
Common Mistakes
This problem tests the thermodynamic stability of high oxidation states stabilized by fluorine's immense lattice energy.
The primary trap is the 'Hidden Variable' of the reference electrode: students often attempt to calculate the absolute half-cell potential by erroneously incorporating the solvation energy of the fluoride ion in the melt.
However, when referenced against the standard fluorine electrode in the same medium, the solvated fluoride ion cancels out of the overall cell equation.
Furthermore, it highlights that despite a massive 4th ionization energy, the state is thermodynamically stable against reduction due to the highly exothermic lattice energy of MF4, resulting in a negative reduction potential.
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | D and F Block Elements - Class 12 |
| Concept | Stability of High O.S. Fluorides/Oxides |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |