J.R. S. answered 02/21/20
Ph.D. University Professor with 10+ years Tutoring Experience
Let's first write a correctly balanced equation for this reaction:
Mg(s) + 2AgNO3(aq) ==> 2Ag(s) + Mg(NO3)2(aq)
Now, using stoichiometry we can find the moles of silver (Ag) produced (assuming AgNO3 is not limiting)
Moles of Mg present = 15.00 g Mg x 1 mol Mg/24.31 g = 0.6170 moles Mg
Moles Ag produced = 0.6170 mol Mg x 2 mol Ag/mol Mg = 1.234 moles Ag (to 4 sig.figs.)