Question

What is the density of an aqueous solution that is 50.0% KOH by mass and has a KOH concentration of 13.39 M?

Answer 1

Answer:

Density = 1.56 g/mL

Explanation:

We have two sort of concentrations in here, so let's combine them.

% by mass means grams of solute in 100 g of solution

M means, moles of solute in 1L of solution.

We know that our solute is KOH (Molar mass = 56.1 g/mol)

We convert the moles of solute to grams:

56.1 g/mol . 13.9 moles = 779.79 g

Now, we know that 50 g of solute are in 100 g of solution

Then, 779.79 g of solute will be contained in (100 . 779.79)/50 = 1559.58 g of solution

Density = mass / volume

1559.58 g of solution / 1000 mL of solution = 1.56 g/mL