High Boiling Points and Bond Strengths  [ENDORSED]

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Sarah Bui 2L
Posts: 61
Joined: Fri Sep 28, 2018 12:29 am

High Boiling Points and Bond Strengths

Postby Sarah Bui 2L » Sun Nov 11, 2018 11:06 pm

I just wanted to make sure I was understanding this correctly, in class I believed he used an example of pentane and 2,2-dimethylpropane and that pentane was rod-shaped. It is because of the higher boiling point (rod-shaped) that the bonds are harder to break versus the spherical shape?
Last edited by Sarah Bui 2L on Mon Nov 12, 2018 1:08 pm, edited 1 time in total.

danicatran4
Posts: 35
Joined: Fri Sep 28, 2018 12:17 am

Re: High Boiling Points and Bond Strengths

Postby danicatran4 » Sun Nov 11, 2018 11:28 pm

I believe that it's the other way around, because the rod-shaped bonds are stronger, the boiling point is higher. However, I don't understand why a rod-shaped structure would have stronger bonds.

Elaine Pham 2E
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Re: High Boiling Points and Bond Strengths  [ENDORSED]

Postby Elaine Pham 2E » Mon Nov 12, 2018 10:48 am

The rod shaped molecules have stronger bonds than the spherical ones because in the rod shaped molecules, there is more contact between the molecules and more surface area interacting with each other. As a result, the bond is shorter between the two molecules and stronger.
As a result of the stronger bond between the rod shaped molecules, the state of matter is more "solid" and it is thus harder to boil the rod shaped molecule, resulting in higher boiling point.

Kirsty Star 2H
Posts: 48
Joined: Fri Sep 28, 2018 12:24 am

Re: High Boiling Points and Bond Strengths

Postby Kirsty Star 2H » Mon Nov 12, 2018 1:34 pm

Do higher melting points work in the same way? Stronger bonds means higher melting point?

Chem_Mod
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Re: High Boiling Points and Bond Strengths

Postby Chem_Mod » Wed Nov 14, 2018 9:33 am

Yes, boiling point and melting point correlate exactly the same. Both of these transition points require breaking intermolecular forces. In the case of melting point, we are going from a solid to a liquid, while a boiling point goes from liquid to gas.


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