If your favorite silver jewelry ever tarnishes and you happen to have some aluminum foil on hand, you can actually get rid of some of that tarnish. The tarnish here is actually silver sulfide. If you put the jewelry and aluminum into a dish with enough water to cover them both, the following reaction will occur: 3Ag2S + 2Al --> 6Ag + Al2S3. If you have a total of 5.0 g of Al foil accessible to you, how many grams of Ag2S (thus, loosely speaking, how much jewelry) could you theoretically "clean"?

1 answer

how many moles in 5g of Al?
The equation says you will use 3/2 that many moles of Ag2S
So, convert that back to grams of Ag2S

of course, the amount of jewelry will be proportional to its surface area, not its volume.