How many grams of silver nitrate must react to give 67.5 grams of Ag according to the balanced equation.
Cu(s) + 2 AgNO3(aq) --> Cu(NO3)2(aq) + 2 Ag(s)
All of these stoichiometry problems are worked the same.
step 1. Write and balance the equation.
step 2. Convert what you have to mols. For solids it is mols = grams/molar mass. For solutions it is M x l = mols.
step 3. Convert mols of what you have to mols of what you want using the coefficients in the balanced equation from step 1.
step 4. Convert mols of what you have to grams by g = mols x molar mass.