posted by stacy on .
silver ions in a solution of silver salts can be recovered by immersing copper metal in the solution. crystals of pure silver are deposited on the silver metal. design an experiment to determine the number of moles of silver atoms that form describe the procedure materials and safety procedure. explain the required calculations
First, I think you mean the silver plates out onto the copper metal.
There may be an easier way to do this and I've not done an experiment like this but can't you do this?
Cu ==> Cu^+2 + 2e
Ag^+e ==> Ag
Therefore, if you weigh the copper strip initially, some of the copper metal will go into solution and silver will replace it. The equations tell us that 1 mole Cu goes into solution for every 2 moles Ag that come out. The extra mass of the copper strip, after plating some silver, will be due to -x moles Cu and + 2x moles Ag.
For example, suppose the strip of copper had a mass of 1.00 g initially. When plated, the mass is 1.100 grams; therefore, the 0.100 g is due to the loss of some Cu and the acquisition of some Ag.
-xmoles Cu + 2x moles Ag = 0.1 gram.
Now change that to grams so grams = grams.
-x*molar mass Cu + (2x*molar mass Ag) = 0.100 gram.
Solve for x = moles Cu
Then 2x = moles Ag.
Wouldn't that work?
There may be a much less complicated way to do it but this is the one that came to my mind. You will need to fill in all of the pieces, the procedure, etc but this is the general idea.
If another tutor checks this out and finds I've made an "illegal" assumption, I'm sure we will hear about it, at least I hope so.