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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: mathguy on April 05, 2011, 10:06:51 PM

Title: electrochemical cells
Post by: mathguy on April 05, 2011, 10:06:51 PM

A galvanic cell consists of a cadmium cathode immersed in
a CdSO4 solution and a zinc anode immersed in a ZnSO4
solution. A salt bridge connects the two half-cells.
(a) Write a balanced equation for the cell reaction.
(b) A current of 1.45 A is observed to flow for a period
of 2.60 hours. How much charge passes through the
circuit during this time? How many moles of electrons
is this charge equivalent to?
(c) Calculate the change in mass of the zinc electrode.
(d) Calculate the change in mass of the cadmium electrode.

I am trying to find help for my biologist fiance right now. She's having a breakdown because this third part of general chemistry is her last course at The University of Chicago and she can't figure out how to answer this question. Any help is more than appreciated. Thank you.

Title: Re: electrochemical cells
Post by: opti384 on April 06, 2011, 12:59:58 AM

First start with the equation. Try to figure out what happens at the cathode and anode each.

Title: Re: electrochemical cells
Post by: Borek on April 06, 2011, 05:27:07 AM

Also, you will need definition of current (charge per time) and Faraday's law of electrolysis.