Question

What is the molarity of a 250.0 milliliter aqueous solution of sodium hydroxide thay contains 15.5 grams of solute. A) 6.2 M B) 0.00155 M C) 0.062 M D) 1.55 M E) 62 M

Answer 1

Hey there:

Molar mass NaOH = 39.997 g/mol

Number of moles:

n = m / mm

n = 15.5 / 39.997

n = 0.387 moles

Volume in liters:

250.0 mL / 1000 => 0.25 L

Therefore:

M = n / V

M = 0.387 / 0.25

= 1.55 M

Answer D

hope this helps!