How many moles of ethylene glycol must be dissolved in 500 g of water (Kf = 1.86) to lower the freezing point to -5.00 0C?

3 answers

delta T = Kf*molality
Plug in 5.00 C for delta T, 1.86 for Kf and calculate molality.
Then molality x kg solvent x molar mass = grams.
You know molality, kg solvent, and molar mass. Calculate grams.

Post your work if you get stuck.
delta T = Kf*molality
Plug in 5.00 C for delta T, 1.86 for Kf and calculate molality.
Then molality x kg solvent x molar mass = grams.
You know molality, kg solvent, and molar mass. Calculate grams.

molar mass? where did u got the molar mass from ?
answered above.