It is likely due to the greater electronegativity of oxygen 3. This is an amazing reference that simplifies properties affecting boiling point, which can be confusing when it comes to the many factors that can come into play!! Thank you to whoever made it!! Based on the information i have seen it looks like pentane has a higher boiling point than di-ethyl ether, based on actual BP but your information tells me that it should be otherwise as diethyl ether has dipole-dipole interactions and pentane has van der waal forces.
Could you clear up for me which should actual have the higher BP and give a reason for the answer? Excellent point!
Interestingly the boiling point of tetrahydrofuran C4H8O is 66 deg C, because the ring gives it a permanent dipole moment. Higher molecular weight is one thing. If we have a molecule with hydrogen bond and one alkane. If alkane has greater molecular weight than hydrogen bond, which on has highest boiling point?
Hi thanks for this info helps a lot but I have a question. It concerns organic compounds. Say you have a ketone such as heptanone. So the boiling point of this compound should be relatively high because it has a large surface area and it is a polar molecule so there are dipole -dipole forces present. Now take a alcohol that is a shorter chain such as propanol.
Alcohol should have a higher boiling point because it has a hygrogen bond. But the propanol molecule is a much shorter chain so it has a smaller surface area than the heptanone. So how can we work out which one has a higher boiling point? In this case heptanone has a higher boiling point than propanol but I would like an explanation as to why.
The key takeaway from this article is that if all variables except one are the same, you can predict boiling points based on these concepts. Generally you just want to know the impact of each variable individually.
Keep up the fantastic work. Dipole-induced dipole is describing the attractive forces between a polar molecule dipole and an induced dipole dispersion, london, van der waals. Instead of looking at one isolated force such as disperson , dipole-induced dipole is describing two that are attracted to eachother…temporarily in the case of induced dipole. I cannot not leave a comment. What a great summary, and really reafable. Thanks James! Now iam clear about the concepts.
Please do keep posting such concepts. Given 3 alcohols : tert-butyl, sec-butyl, and n-butyl with their respective boiling point measurements at : 82C, C, and C. What creates the differences in their boiling point values? Is it the location of the hydroxyl groups?
The key factor will be surface area. I am having a little problem in understanding the melting point trends……why the following melting point increase is uneven………. Thank you! I normally hate and can barely understand chemistry but this made it very clear and easy to understand so thank you :.
Why does NO2 have a greater boiling point than SO2? Both are polar, dipole-dipole interactions, but SO2 has a greater dipole moment, greater molar mass, and greater surface area. I know NO2 is a radical, does that affect boiling point? Hey there, just wanted to stop by to say how much I appreciate this website. You have an exceptional ability to present material in a concise, understandable fashion. Why does trans butene has higher melting point but lower boiling point than cis butene?
Is this because of dipole moment? I want to know, how water content in crystallized substance affects its melting point. Nice, really appreciate your broadness without sticking to a job.
Society might wish in a bigger way than what you had opted earlier…One thing Dear professor James , when we are discussing about boiling point , I have to say that, does the factors like sterically hinderedness of a molecule come to scenario or we shall ignore about the effects. Let you know that I am working as an assistant professor in the University, India. Welcome you and your page with open arms.
How chlorine will affect the boiling point of a alkyl chain for exemple 1-chloro-octane compare to octane? And for 1-bromo-octane? And for 1-bromochloro-octane?
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