The balanced chemical equation for the reaction of copper (Cu) and silver nitrate (AgNO3) is shown below.
Cu + 2AgNO3 → 2Ag + Cu(NO3)2
How many moles of copper must react to form 3.50 mol of Ag?

1.75 moles Cu

Explanation: From the balanced equation we can solve the number of moles by using the stoichiometric factor or mole ratio between Ag and Cu which is 2 : 1.

Cu + 2 AgNO3 => 2 Ag + Cu( NO3)2

3.50 moles Ag x 1 mole Cu / 2 moles Ag

= 1.75 moles Cu