Question

Dissolving 16 g of urea (MW= 60 g/mol) in 39 g of water produces 42.3 ml of solution. Determine the molarity of this solution

Answer 1

Hey there!:

Molar mass urea = 60 g/mol

Number of moles of solute:

moles solute = mass solute / molar mass

moles solute = 16 / 60

moles solute => 0.2666 moles of urea

Volume in liters:

42.3 mL / 1000 => 0.0423 L

Therefore:

Molarity = moles of solute / volume of solution

Molarity = 0.2666 / 0.0423

= 6.302 M

Hope that helps!