Will 100g of copper completely replace all the silver in 200g of silver nitrate

Answer 1

A limiting reagent problem.
2AgNO3 + Cu ==> Cu(NO3)2 + 2Ag
mols Cu = grams/atomic mass = ?
mols AgNO3 = grams/molar mass = ?

Using the coefficients in the balanced equation:
Convert mols Cu to mols Ag
Convert mols AgNO3 to mols Ag

The smaller number wins; i.e., if AgNO3 is the limiting reagent (the smaller number mols of Ag produced) then that amount of Cu will replace all of the Ag in AgNO3.