Question

What is the molarity of a 2.0 L sodium hydroxide solution containing 10.0 grams os solute?

Answer 1

molar mass NaOH = 39.997 g/mol

number of moles:

n = mass of solute / molar mass

n = 10.0 / 39.997

n = 0.2500 moles

Therefore:

Molarity = moles of solute / volume ( L )

M = 0.2500 / 2.0

M = 0.13 mol/L