Calculate the concentration of nitric acid in moles per litre in a sample which has a density `1.41 g mL^(-1)` and the mass percent of nitric acid in it being `69%`.

Explanation

Mass percent of 69 % means that 100 g of nitric acid solution contain 69 g of nitric acid by mass. Molar mass of nitric acid `(HNO_(3)) = 1 + 14 + 48 = 63 g mol^(-1)`
Moles in 69 g `HNO_(3) = (69 g)/(63 g mol^(-1)) = 1.095` mole
Volume of 100 g nitric acid solution `= (100 g)/(1.41 g m L^(-1)) = 70.92 mL = 0.07092 L`
Conc. of `HNO_(3)` in moles per litre `= (1.095)/(0.07092 L) = 15.44 M`