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Question #44732
The Question
A galvanic cell is constructed at using Zirconium and Hafnium electrodes immersed in their respective hydroxide suspensions:
Due to the lanthanoid contraction, and exhibit nearly identical atomic/ionic radii and chemical properties. Consequently, assume their standard reduction potentials are equal () and their hydroxide solubility products are identical (). Assuming is the only soluble metal species, calculate the cell potential () at .
(Given: )
Options
- A.
- B.
- C.
- D.
Check Your Answer
Correct Answer
Step-by-Step Solution
Explanation
How the Examiner Thinks
Exception_Exposure
Learn to identify edge cases and boundary exceptions that JEE examiners hide in math problems.
Concepts Behind This Question
Nernst Equation Concentration Dependence|Post-Lanthanoid Radii Equality|Lanthanoid Contraction cause
Why This Question Is Tricky
Common Mistakes
This problem tests the intersection of Periodic Trends (Lanthanoid Contraction) and Electrochemistry.
Students often panic when presented with two different metals without explicit values.
The 'Hidden Variable' is recognizing that the Lanthanoid Contraction equalizes the standard reduction potentials and solubility products of Zr and Hf, effectively reducing the system to a concentration cell ().
Furthermore, it traps students who fail to correctly apply the 4th power dependence of the hydroxide concentration in the expression or who mistakenly use instead of to find the reaction quotient .
Quick Facts About This Question
Question Information
| Subject | Chemistry |
| Chapter | Electrochemistry - Class 12 |
| Concept | Nernst Equation Concentration Dependence |
| Difficulty | 8 |
| Cognitive Load | 7 |
| Target Solve Time | 160 sec |
| Access | Free |