1.The balanced  chemical equation is as below
Cu +  2 Ag(NO)₃ → Cu(NO₃)₂  +2 Ag
2.The  much silver  produced  is  50.9 g
Step 1: find the  moles of Cu
moles =  mass÷  molar mass
 from periodic table the molar mass of Cu = 63.5 g/mol
moles is therefore = 15.00 g÷ 63.5 g/mol = 0.236  moles
Step 2: use the mole ratio to determine the  moles of Ag
from equation above  Cu:Ag  is 1:2
therefore the moles of Ag  =0.236  moles  x 2/1 =0.472  moles
Step 3: find the mass  of Ag
mass = moles x molar mass
from periodic table  the molar mass of Ag =107.87 g/mol
mass  = 0.472  moles x 107.87 g/mol = 50.9 g
3.  The  much  silver  collected worth is  1.797 oz
 convert  50.9 g  to oz
that is  1 gram = 0.0353 oz
     50.9 grams =?  oz
by cross multiplication
={(50.9 grams x 0.0353 oz) / 1 Â gram} Â =1.797 oz