The percent by mass of nitric acid in the mixture is 3.36 %
2 HNO3 + Ba(OH)2 --->Ba(NO3)2 + 2H2O
so 1 mole Ba(OH)2 neutralizes 2 mol HNO3
moles of Ba(OH)2 present = molarity of base* volume of base
= 0.229 M * 15.6 ml
= 3.5724 milli mols
mols of HNO3 neutralized = 2* mols of Ca(OH)2 used
= 2* 3.5724 milli mols = 7.1448 x10^-3 mols
molar mass of HNO3 = 63.01 g/mol
mass of HNO3 present = molar mass * mols of HNO3
= 63.01 g/mol * 7.1448 x10^-3 mols
=0.4502 g
mass of sample = 13.4 g
mass % = mass of HNO3/mass of sample * 100
= 0.4502/13.4 *100
= 3.36 %
Nitric acid is a colorless, fuming, and distinctly corrosive liquid that could be a not unusual laboratory reagent and an important commercial chemical for the manufacture of fertilizers and explosives.
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