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Grade 12th passPhysical Chemistry

An electric current is passed through a copper voltmeter and a water voltmeter connected in series. If the copper of the copper voltmeter now weights 16 mg less, hydrogen liberated at the cathode of water voltmeter measures at STP?

Profile image of Maliha
8 Years agoGrade 12th pass
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1 Answer

Profile image of Saurabh Kumar Sinha
7 Years ago
Cu ---->  Cu2+   +  2e-
63.5g Cu is given by 2F
So,16g Cu gives 2/63.5 * 16 F
 
Now, 2H+ -----> H2  +  2e-
2F liberated 22.4L H2
So 2/63.5 * 16F liberated 22.4/2 * 32/63.5 = 5.6L H(approx.)