In a classroom demonstration of a redox reaction, a professor set up a voltaic c
ID: 1065750 • Letter: I
Question
In a classroom demonstration of a redox reaction, a professor set up a voltaic cell with a copper metal
anode and a silver metal cathode. The two electrodes were in contact with solutions of the corresponding
metal ions, Cu2+ and Ag+. During the lecture, the crystals of silver metal deposited on the silver electrode as
the copper solution turned a darker blue. The added silver crystals had a mass of 2.68 g after 50.0 minutes of
lecture. What was the average current that the cell produced?
A 0.799 A
B 2.40 A
C 47.9 A
D 1.60 A
E 0.479 A
Explanation / Answer
correct answer : A) 0.799 A
mass of silver = 2.68 g
time = 50.0 min = 50 x 60 = 3000 sec
equivalent weight = 107.8 / 1 = 107.8
W = E x i x t / 96485
2.68 = 107.8 x i x 3000 / 96485
i = 0.799 A
current = 0.799 A