Question

How many grams of copper are required to replace .5 moles of silver nitrate (which is dissolved in water), assuming a copper (II) product?

Answer 1

You need 16 g of copper.

Explanation:

The equation for the reaction is

`"2Ag"^+("aq") + "Cu(s)" → "2Ag(s)" + "Cu"^(2+)("aq")`

Step 1. Calculate the moles of `"Cu"` required.

`0.5 color(red)(cancel(color(black)("mol Ag"^+))) × "1 mol Cu"/(2 color(red)(cancel(color(black)("mol Ag"^+)))) = "0.25 mol Cu"`

Step 2. Calculate the mass of `"Cu"`.

`0.25 color(red)(cancel(color(black)("mol Cu"))) × "63.55 g Cu"/(1 color(red)(cancel(color(black)("mol Cu")))) = "16 g Cu"`