Sodium hydroxide is available commercially as a 50.0% by weight aqueous solution.The density of the solution is 1.53 g/mL.Calculate the molarity of this sodium hydroxide solution.
A)0.450 M
B)19.1 M
C)25.0 M
D)125.M

Question

Quizplus · Accepted Answer

Molarity (M) is defined as moles of solute per liter of solution.

To calculate the molarity of the sodium hydroxide solution, we need to first find the number of moles of NaOH in 1 liter of solution.

Since the solution is 50.0% by weight, we know that 1 L of the solution contains:

- mass of NaOH = 0.5 x 1000 mL x 1.53 g/mL = 765 g
- number of moles of NaOH = mass / molar mass = 765 g / 40.00 g/mol = 19.125 mol

Therefore, the molarity of the solution is:

M = number of moles / volume of solution = 19.125 mol / 1 L = 19.1 M

So, the correct answer is B.

Sodium Hydroxide Is Available Commercially as a 50