<p>Okay... there was this question I encountered on Boiling/Freezing points that required background knowledge. BP/FP type experiments are quite common so I want to get this cleared up</p>
<p>Ethanol/ BP=65 / MP = -114
1-propanol / BP = 78/ MP= -126</p>
<p>The table did not give any data on freezing points. The question asked "which one of the alcohols listed in table 1 has the lowest freezing point? </p>
<p>Using logic, I thought that it would be the one with the lowest melting and boiling point. However, there was no such choice; ethanol had the lower boiling point, and 1-propanol had the lower melting point. I guessed ethanol and got it wrong. How do you determine lowest freezing point based on given BP and MP's?</p>
<p>Pretty sure it would be the one with the highest boiling point, actually, from what I remember in Chem. I don’t remember what I put but I got a perfect score, so.</p>
<p>Boiling Point and Freezing point vary inversely. For example, in substance A, if the boiling point increases, the freezing point will increase (like go from -5 to -10). So in this question, the boiling point of ethanol is 65 and the Boiling point of 1-propanol is 78. Therefore because 1- propanol has the higher boiling point, 1-propanol would have a a lower freezing point than ethanol.</p>
<p>Aren’t melting and freezing points the same???
Water freezes at 32F, but also melts at that point.</p>
<p>Edit: therefore, 1-prop has both the lowest melting and freezing points</p>
<p>Freezing point = melting point, so 1-propanol is the answer at -126.</p>
<p>also, if you took chem, 1-propanol has a higher molecular weight (aka more london dispersion forces), so it would have a lower freezing point</p>
<p>Oh lol melting point = freezing point. what a damn question lol</p>
<p>This does seem to be a more difficult question for the science section. I probably would have stumbled too, because I didn’t realize that melting point = freezing point until I got into AP chem, lol :)</p>
<p>Soooooooo tricky. I still can’t believe they did that!</p>
<p>if thats an ACT science question, it must be really easy.</p>
<p>^I’m not exactly sure what the point of that post was.</p>
<p>Most people do not find the actual questions on the science section to be overly difficult- they find it hard to work under the time constraints, which require you to move quickly and not focus on one question very long.</p>