-->

Solutions

Question
CBSEENCH12005724

Concentrated nitric acid used in the laboratory work is 68% nitric acid by mass in aqueous solution. What should be molarity of such sample of the acid if the density of solution is 1.504 g mL–1?

Solution
Answer: 

68% by mass implies that 68 g of HNO
are present in 100 g of solution.
Volume of solution = Mass of solutionDensity of solution

                             = 100g1.504 g mL-1= 66.5 cm3 = 0.665 L.
Molar mass,
        MB of NHO3 = 1+14+48 = 63.
           Molarity = ωAMB×V               = 68 g63 g mol-1 × 0.0665               = 16.23 M.