Boiling point and molality help?

Question

List the following aqueous solutions in order of increasing boiling point: 0.040 m glycerin, 0.020 m KBr, 0.030 m phenol, C6H5OH. How do you figure this out? Thanks

Answer 1

Delta T = kf x m x i

i = 1 for glycerin ( non electrolyte)

delta T = 0.512 x 0.040 = 0.0205 °C

boiling point = 100 + 0.0205 = 100.0205 °C

i = 2 for KBr ( KBr >> K+ + Br-)

delta T = 0.512 x 0.020 x 2 = 0.0205 °C

boiling point = 100.0205 °C