Question

A 14.1% by mass HClO3 solution has a density of 1.1690 g/mL. What is the concentration of this solution in molarity?

Answer 1

Answer:

[ HClO₃] = 1.93M

Explanation:

X % by mass, means that in 100 g of solution, we have X g of solute.

In this case, 14.1 g of HClO₃ are contained in 100 g of solution.

Density always referrs to solution. Let's calculate the volume of solution.

Solution density = Solution mass / Solution volume

1.1690 g/mL = 100 g / Solution volume

Solution volume = 100 g /1.1690 g/mL → 86.2 mL.

For molarity we must get moles of solute and volume of solution (L), because molarity is mol/L

Let's convert the mL of solution in L

86.2 mL . 1L / 1000mL = 0.0862 L

Now, let's determine the moles of solute. (Mass / Molar mass)

14.1 g / 84.45 g/mol = 0.167 moles

Molarity is mol/L →  0.167 moles / 0.0862 L = 1.93M