Question

What mass of copper is required to replace silver from 4.00g of silver nitrate dissolved in water?

Cu + AgNO3 → Cu(NO3)2 + Ag

Answer 1

4.00 / 169.87 = 0.0235 mole AgNO3

We require 0.0235 mole Cu

0.0235 x 63.546 = 1.26 g Cu

http://www.funqa.com/chemistry/519-chemistry-3.html

Answer 2

It is true that 4g of AgNO3 is 0.0235 mol. But to continue we must balance the reaction.

Answer 3

Cu + 2AgNO3 -> Cu(NO3)2 + 2Ag

Answer 4

Make sense so far?

Answer 5

Yeah it makes sense

Answer 6

I'm supposed to solve this using dimensional analysis but I don't really know how to set the problem up that way.

Answer 7

Using dimensional analysis, I would do something like this:
4g AgNO3 (1 mol /169.87g) (1 mol Cu/2 mol AgNO3)(63.546 g Cu/1 mol Cu) = number of grams of Cu

Answer 8

Using dimensional analysis, all of the other units cancel.

Answer 9

Ok, I tried it that way and got 0.7467 g of Cu as my answer. I don't know if that's correct though.

Answer 10

I get 0.748g Cu rounded to three sig figs.

Answer 11

I tried it again and got the same answer as you. I must have messed up somewhere before. Thanks for your help!

Answer 12

No worries. :) Happy studies!