JEE Main 2020ChemistryElectrochemistryHardNumerical

JEE Main 2020Electrochemistry Question with Solution

JEE Main 2020 (09 Jan Shift 1)

Question

108 g of silver (molar mass 108 gmol-1 ) is deposited at cathode from AgNO3aq solution by a certain quantity of electricity. The volume (in L ) of oxygen gas produced at 273 K and 1 bar pressure from water by the same quantity of electricity is ________

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Show full solutionCorrect answer: 5.66
Correct answer
5.66

Step-by-step explanation

nAgdeposit=108108=mole
Ag++e-Ag
1F charge is required to deposit 1 mole of Ag
H2O 12O2+2H++2e-
2F charge is required to deposit 12mole
1F charge will deposit 14mole of O 2   gas.
VO2=nRTP
=14×0.0821×2731=14×22.4
VO2=5.6 L

Faraday's second law of electrolysis states that, when the same quantity of electricity is passed through several electrolytes, the mass of the substances deposited are proportional to their respective equivalent weight.

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About this question

This is a previous-year question from JEE Main 2020, covering the Electrochemistry chapter of Chemistry. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.