Boiling Point comparison

[Czarcasm]

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Why does Ethylene Glycol (the component of antifreeze), have a lower freezing point than water? Wouldn't you expect a higher melting/freezing point and boiling point due to the increased presence of hydrogen bonding and molecular weight?

Wikipedia says:

Melting point−12.9 °C; 8.8 °F; 260.2 K
Boiling point197.3 °C; 387.1 °F; 470.4 K

Boiling point of ethylene glycol is higher as predicted, but the melting/freezing point is less than water (lower than 0 °C). That's a little contradicting, don't you think?

 

[Czarcasm]

Does this have anything to do with colligative properties (ie. freezing point depression, boiling point elevation) when adding solutes to a solution (in this case ethylene glycol to water)? And should we expect all miscible solutions to produce a lower melting/freezing point than water?

 

[Teleologist]

Does this have anything to do with colligative properties (ie. freezing point depression, boiling point elevation) when adding solutes to a solution (in this case ethylene glycol to water)? And should we expect all miscible solutions to produce a lower melting/freezing point than water?

Here, I'll give you the Straight Dope (tm):

Yes, the answer has to do with colligative properties. Yes, all solutions have lower freezing points and higher boiling points than their pure solvents.

I hope ignorance was fought.

 

[Czarcasm]

Here, I'll give you the Straight Dope (tm):

Yes, the answer has to do with colligative properties. Yes, all solutions have lower freezing points and higher boiling points than their pure solvents.

I hope ignorance was fought.

Haha, thanks for answering. I should listen to my instincts more often! I tend to over analyze things and I think that's what hurts me most.