In: Chemistry
A 12% by mass solution of acetone (C3H6O) in water has a density of 0.9849 g/mL at 20˚C. What is the molality and molarity of this solution?
let volume = 1L = 1000ml
mass of solution = volume * density
= 1000*0.9849 = 984.9g
mass of acetone = 0.12*984.9 = 118.188g
no of moles of acetone = W/G.M.Wt
= 118.188/58 = 2.04moles
molarity = no of moles/volume of solution in L
= 2.04/1 = 2.04M
molality = M*1000/1000*d -M*gram molar mass
= 2.04*1000/1000*0.9849-2.04*58
= 2040/866.58 = 2.35m