Answer:
0.7482 g grams of copper are required .Explanation:
[tex]Cu(s)+2AgNO_3(aq)\rightarrow Cu(NO_3)_2(aq)+2Ag(s)[/tex]
Moles of silver nitrate =[tex]\frac{4.00 g}{169.87 g/mol}=0.0235474 mol[/tex]
According to reaction , 2 moles of silver nitrate reacts with 1 mol of copper.
Then 0.0235 mol of silver nitrate will react with:
[tex]\frac{1}{2}\times 0.0235474 mol=0.0117737 mol[/tex] of copper
Mass of 0.0117737 mol of copper = 0.117737 mol × 63.55 g/mol = 0.7482 g
0.7482 g grams of copper are required .