What volume of distilled water should be diluted with 100 g of 9% sodium chloride solution to obtain 0.9% saline?

Find the mass of salt in a 9% solution.

C (NaCl) = m (in-islands) / m (solution) • 100%.

m (NaCl) = 9 * 100/100 = 9 g.

Let’s compose an expression:

Let x be the mass of added water, and the amount of water needed to dilute the solution 100 + x.

0.9% = 9 / (100 + x) • 100%,

0.009 = 9 / (100 + x),

0.9 + 0.009x = 9,

x = 900 g.

Since the density of water is 1, the volume will be equal to the mass.

This means that to obtain a solution with a mass fraction of salt of 0.9%, it is necessary to add 900 ml of water.