[chukklz]

Hard candies are produced by boiling a solution of sucrose (C₁₂H₂₂O₁₁, molar mass = 342.30g/mol) in water until it reaches a temperature of 150°C. The K_b for water is 0.51°C/m. What is the molality of the sugar solution when it boils at 150°C? How much sucrose in grams is present in 1 kg of the solution? What is the mass percent of sucrose in the solution?

To try and get the molality I divided the change in temp for boiling which is 50 and divided it by 0.51 and got 98. Is that right? If so how do I use this to figure out the rest of the problem?

[Ciubba]

That is correct.

mc=m*i

So, if you know the vant hoff factor, you can find the molality of the sugar water solution. Given that molality is mol solute/ kg solvent, you should be able to relate molality to mass and mass percentage.