Asked by Michelle
A solution is prepared with 50.0 g of HNO3 and 130.0 g of H2O. It has a density of 1.21 g/mL. What is its molarity (M)?
Answers
Answered by
DrBob222
%by mass = (50 g HNO3/180 g soln)*100 = 27.777% which I would keep although that is too many significant figures (s.f.). (I would round at the end.).
density = 1.21 g/mL; therefore, 1000 mL has a mass of 1.21 g/mL x 1000 mL = 1210 grams.
That is 27.777% HNO3; therefore, g HNO3 there is 1210 x 0.27777 = 336.1 grams HNO3.
How many moles is that?
moles = grams/molar mass = ??
That many moles in 1 L soln is that molarity. Round your answer to 3 s.f.
density = 1.21 g/mL; therefore, 1000 mL has a mass of 1.21 g/mL x 1000 mL = 1210 grams.
That is 27.777% HNO3; therefore, g HNO3 there is 1210 x 0.27777 = 336.1 grams HNO3.
How many moles is that?
moles = grams/molar mass = ??
That many moles in 1 L soln is that molarity. Round your answer to 3 s.f.