Answer:
[HClO₄] = 11.7M
Explanation:
First of all we need to know, that a weight percent represents, the mass of solute in 100 g of solution.
Let's convert the mass to moles → 70.5 g . 1mol/100.45 g = 0.702 moles
Now we can apply the density to calculate the volume.
Density always refers to solution → Solution density = Solution mass / Solution volume
1.67 g/mL = 100 g / Solution volume
Solution volume = 100 g / 1.67 g/mL → 59.8 mL
To determine molarity (mol/L) we must convert the mL to L
59.8 mL . 1L/1000mL = 0.0598 L
Molarity → Moles of solute in 1L of solution → 0.702 mol / 0.0598 L = 11.7M