posted by London .
Impure sample of table salt that weighed 0.8421g, when dissolved in water and treated with excess AgNO3, formed 2.044g of AgCl. What is the percentage of NaCl in the impure sample?
Do I need the molecular weight to start this equation? Where do I start?
Same place you started for BaSO4 problem I worked for you.
%NaC= (mass NaCl/mass sample)*100
mass sample = 0.8241 g.
mass AgCl = 2.044 g
moles AgCl = g/molar mass = ??
moles Cl is the same as moles AgCl. moles NaCl is same as mols AgCl.
moles NaCl x molar mass NaCl = mass NaCl.
Substitute into the top equation and solve for %NaCl.