x mol 0.005 mol
AgNO3+KCl = KNO3+AgCl↓
1 mol 1 mol
n(AgCl) = m(AgCl) / M(AgCl) = 0.716 g / 143.5 g/mol = 0.005 mol
x mol / 1 mol = 0.005 mol / 1 mol
x = (0.005 mol * 1 mol) / 1 mol
x = 0.005 mol, n(AgNO3) = 0.005 mol
m(AgNO3) = n(AgNO3) * M(AgNO3) = 0.005 mol * 170 g/mol = 0.85 g
m(AgNO3) = 0.85 g