A sample of nitric acid is 55 per cent by mass. Calculate the mass of nitric acid present in 100 cm of the sample if its density is 1.36 g cm^(-3).

A sample of nitric acid is 55 per cent by mass. Calculate the mass of

1.	A sample of nitric acid is 55 per cent by mass. Calculate the mass of nitric acid present in 100 cm of the sample if its density is 1.36 g cm^(-3).
Answer» Solution :Since, the given sample is 55% by mass, 100 g of the sample would CONTAIN 55 g of `HNO_3`. Since, DENSITY `=("mass")/("volume")` Therefore, the volume of 100 g of the sample `=("mass")/("density") = 100/(1.36) = 73.5 cm^(3)` Thus,73.5 cm of the given sample contains 55 g of `HNO_3`. Hence, the mass of `HNO_3` present in 100 cm of the sample `=55/(73.5) XX 100 = 74.8 g`