A certain current liberates 0.504 g of hydrogen in 2 hours. How many grams of copper can be liberated by the same current flowing for the same time in aqueous CuSO4 solution?
Correct answer: B. 16
- A. 12.7
- B. 16
- C. 31.8
- D. 63.5
Explanation
To determine the mass of copper liberated, we use Faraday's laws of electrolysis. The amount of substance liberated at an electrode is directly proportional to the quantity of electricity that passes through the electrolyte. Given that 0.504 g of hydrogen is liberated by a certain current in 2 hours, we can use the equivalent weight of hydrogen (1 g/mol) and copper (63.5 g/mol) for calculations. The equivalent of copper in CuSO4 solution is 31.75 g/mol (since copper has a valency of 2). The ratio of the masses of copper and hydrogen liberated is equal to the ratio of their equivalent weights. Therefore, the mass of copper liberated is (31.75/1) * 0.504 = 16 g. Thus, Option B is correct. The other options are incorrect as they do not align with the stoichiometric calculations and principles of Faraday's laws.
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