Posted by Melia on Monday, November 19, 2012 at 2:18am.
A 100.0mL solution containing aqueous HCl and HBr was titrated with 0.1290M NaOH. The volume of base required to neutralize the acid was 47.56mL. Aqueous AgNO3 was then added to precipitate the Cl and Br ions as AgCl and AgBr. The mass of the silver halides obtained was 0.9849 g.
a.)What is the molarity of HBr in the original solution?
b.)What is the molarity of HCl in the original solution?

Chemistry  DrBob222, Monday, November 19, 2012 at 7:06pm
Two equations in two unknowns.
Let X = mols HBr
and Y = mols HCl

equation 1 and 2 follow:
X + Y = 0.1290 x 0.0475
X(molar mass AgBr) + Y(molar mass HCl) = 0.9849

Solve for X and Y, then M HCl = mols HCl/L and M HBr = mol HBr/L