Stoichiometry help

Question

How many grams of copper react to give 1.80 g of Ag?

Cu(s)+2AgNO3(aq)→Cu(NO3)2(aq)+2Ag(s)

Express your answer with the appropriate units.

Answer 1

Cu(s)+2AgNO3(aq)→Cu(NO3)2(aq)+2Ag(s)

From this balanced equation you see that 1 MOLE of Cu produces 2 MOLES of silver. Assuming that the AgNO₃ is not in limiting supply, you can approach this problem as follows.

Moles of Ag produced = 1.80 g Ag x 1 mole/108 g = 0.0167 moles

Moles Cu needed = 0.0167 moles Ag x 1 mol Cu/2 mol Ag = 0.00833 moles Cu

Mass of Cu needed = 0.00833 moles Cu x 63.5 g/mol = 0.529 g Cu