Question

Calculate the concentration of nitric acid in moles per litre which has a density , 1.41 g/mL. %w/w of nitric acid is

(a) 15.44 M

(b)  0.0 64 M

(c)  0.077 M

(d)  12.87 M

Answer 1

Correct option (a) 15.44 M

• 69% w/w means 100 g nitric acid soution contain 69 g of nitric acid by mass.

:. moles of HNO₃ = 69/63 = 1.095

• Vol. of 100 g nitric acid solution = 100/1.41 = 0.07092 L

:. moles per litre = 1.095/0.07092 = 15.44