Question

Calculate the molarity (M) of a 17.5% (by mass) aqueous solution of nitric acid (HNO3, Mol.mass. = 63 g/mol)

A) 2.74 M
B) 3.04 M
C) 4.33 M
D) 0.274 M
E) The density of the solution is needed to solve the problem

Answer 1

To calculate the molarity of the solution, we use the percentage by mass and the density of the solution to find the mass of nitric acid. Then we convert the mass to moles using the molar mass of nitric acid. Finally, we divide the moles of nitric acid by the volume of the solution to find the molarity.

Step-by-step explanation:

To calculate the molarity of the nitric acid solution, we first need to find the number of moles of nitric acid in the solution. We can start by calculating the mass of nitric acid in the solution using the percentage by mass and the density of the solution.

Mass of nitric acid = 17.5% × density × volume

Next, we can convert the mass of nitric acid to moles using the molar mass of nitric acid. Molar mass of HNO3 = 63 g/mol

Moles of nitric acid = mass of nitric acid / molar mass of nitric acid

Finally, we can calculate the molarity using the moles of nitric acid and the volume of the solution.

Molarity (M) = moles of nitric acid / volume of solution

Plugging in the values, we get Molarity = (mass of nitric acid / molar mass of nitric acid) / volume of solution = (17.5% × density × volume) / (molar mass of nitric acid × volume of solution).

Calculating the expression, we find that the molarity of the solution is approximately 3.04 M.