The same amount of electricity (same number of moles ofelectrons) is used to carry out the electrolysis ofPdCl2 (aq) and AgNO3 (aq) solutions inseparate cells. The masses of Pd and Ag produced weremeasured and compared. Which of the following is true aboutthe mass of Pd produced? A. The mass of Pd produced is not related to the mass ofAg B. The mass of Pd produced is approximately half that ofAg C. The mass of Pd produced is approximately twice that ofAg D. The mass of Pd produced is approximately the same as thatof Ag The answer is B, but I don't know how to arrive to theanswer. The same amount of electricity (same number of moles ofelectrons) is used to carry out the electrolysis ofPdCl2 (aq) and AgNO3 (aq) solutions inseparate cells. The masses of Pd and Ag produced weremeasured and compared. Which of the following is true aboutthe mass of Pd produced? A. The mass of Pd produced is not related to the mass ofAg B. The mass of Pd produced is approximately half that ofAg C. The mass of Pd produced is approximately twice that ofAg D. The mass of Pd produced is approximately the same as thatof Ag The answer is B, but I don't know how to arrive to theanswer.
Explanation / Answer
Pd2+ + 2e- Pd Ag+ + 1e- Ag it takes twice as many electrons to reduced the cation to theneutral metal when you are reducing Pd2+ compared to reducingAg+ So you produce twice as many moles of Ag than moles of Pd Also the atomic weights of Ag and Pd are comparable (106 vs 107g/mol), so you really form twice as much mass of Ag than Pd