Chemical Forums
Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: vanillachyrae on February 25, 2013, 07:04:48 AM
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Automotive antifreeze consists of ethylene glycol C2H6O2, a non volatile, non electrolyte. Determine the (a) boiling point (b) freezing point (c) vapor pressure (d) osmotic pressure of a 25.0 % solution of ethylene glycol in water.
I really need help :/ I actually don't know what to do but here's what I got:
25% solution of ethylene glycol, does this mean that there's 25g of ethylene glycol in the solution?Assuming what I'm doing was right, I divided the 25g by FW of C2H6O2 which is 62g so I get 0.403 moles of C2H6O2.
For the freezing point, Tb = Kfm where Kf is 1.86 C/molal right? and m is the molality. I only have the moles of the solute and I don't know if I need to assume that there is 75g of water to get the kg of solvent in molality.
The same goes for the boiling point and osmotic pressure, I'm having problems with the volume of the solution and solvent. And for the vapor pressure do i need to use the formula Psolution = PA + PB?
Please tell me if I got this all wrong or what. :/