30 grams of a compound that does not ionize in H_2O are added to 500 grams of H_
ID: 480886 • Letter: 3
Question
30 grams of a compound that does not ionize in H_2O are added to 500 grams of H_2O. It is found that the freezing point of the solution is lowered by 0.450 K relative to the freezing point of pure H_2O. If the solution is ideal and sufficiently dilute to use the limiting form of the freezing point depression equation, the data show the molar mass of the compound to be greater than 300 g mol^-1. between 250 to 300 g mol^-1. between 200 to 250 g mol^-1. between 150 to 200 g mol^-1. less than 150 g mol^-1.Explanation / Answer
mass of solute = 30 g
mass of solvent = 500g
depression in freezing point = 0.45
Kf of water = 1.86 K Kg/m
We know delat Tf = Kf x m
0.45 = 1.86 x (30/M)(1000/500)
or molar mass M = 248g/mol
Thus the ioption C is correct.
Related Questions
Hire Me For All Your Tutoring Needs
Integrity-first tutoring: clear explanations, guidance, and feedback.
Drop an Email at
drjack9650@gmail.com
drjack9650@gmail.com
Navigate
Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.