H bonding

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Reese - Dis 1G
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H bonding

Postby Reese - Dis 1G » Tue Nov 20, 2018 5:36 pm

How does hydrogen bonding effect boiling and melting points?

Madison Gil 3D
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Re: H bonding

Postby Madison Gil 3D » Tue Nov 20, 2018 5:59 pm

The presence of hydrogen bonds in molecules increases both melting and boiling points because greater intermolecular forces in the molecule will require more energy to be broken apart.

Manu Vohra 1L
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Re: H bonding

Postby Manu Vohra 1L » Thu Nov 22, 2018 2:00 am

Hydrogen bonding results in higher melting and boiling points since it is the strongest type of intermolecular force (other than ionic bonding).

Sarah Jeong 4F
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Re: H bonding

Postby Sarah Jeong 4F » Thu Nov 22, 2018 10:57 am

You can visually see this as a large pot of water(more hydrogen bonds) takes a higher temperature to boil than a small pot of water.

Nicole Lee 4E
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Re: H bonding

Postby Nicole Lee 4E » Fri Nov 23, 2018 1:55 pm

Dr. Lavelle's examples in class were H2O and H2S. H2O has a higher melting point at 0°C and higher boiling point at 100°C compared to H2S which has a melting point of -80°C and boiling point of -60°C. Since H2O has hydrogen bonds, the melting point and boiling point increase.

Alex Alonso - 4F
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Re: H bonding

Postby Alex Alonso - 4F » Fri Nov 23, 2018 3:32 pm

Hydrogen bonding results in higher boiling and melting points

JT Wechsler 2B
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Re: H bonding

Postby JT Wechsler 2B » Fri Nov 23, 2018 4:09 pm

The presence of a hydrogen bond will increase the melting point and boiling point of a substance because there is a stronger attraction between the molecules of the substance.

angelagd3l
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Re: H bonding

Postby angelagd3l » Fri Nov 23, 2018 7:16 pm

the more hydrogen bonds the higher melting points?

Vicky Lu 1L
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Re: H bonding

Postby Vicky Lu 1L » Sat Nov 24, 2018 12:40 am

As hydrogen bonding is on the stronger side of intermolecular forces, it requires more energy to break this bond. This results in high boiling points since it requires more energy to separate the molecules.

BenJohnson1C
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Re: H bonding

Postby BenJohnson1C » Sat Dec 08, 2018 3:36 pm

Why can it only occur with N O and F?

Katie_Duong_1D
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Re: H bonding

Postby Katie_Duong_1D » Sat Dec 08, 2018 4:01 pm

BenJohnson1C wrote:Why can it only occur with N O and F?


Hydrogen bonding only occurs with N O F because these are very electronegative elements. N O F have more electron pulling power, creating a partial positive on the hydrogen and a partial negative on N O F. The electrostatic attraction between H and N O F is stronger than regular London dispersion forces.

JT Wechsler 2B
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Re: H bonding

Postby JT Wechsler 2B » Sat Dec 08, 2018 4:08 pm

The presence of H-bonding increases both the melting and boiling points.

605168557
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Re: H bonding

Postby 605168557 » Sat Dec 08, 2018 5:29 pm

Melting and boiling points result from the intermolecular forces present. Hydrogen bonding as an intermolecular force will increase both melting and boiling points because greater energy is needed to separate the molecules.


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