Energy of Intermolecular Forces

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Elaine Pham 2E
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Energy of Intermolecular Forces

Postby Elaine Pham 2E » Sat Nov 17, 2018 5:09 pm

Why are the energies of the different interactions Dr. Lavelle talked about in class negative?
For example, the energy of an ion-ion interaction is -250 kJ/mol. I am a little confused why it's a negative number and not a positive one.

Mahir_Hasan2C
Posts: 60
Joined: Fri Sep 28, 2018 12:25 am

Re: Energy of Intermolecular Forces

Postby Mahir_Hasan2C » Sat Nov 17, 2018 6:28 pm

They are all negative because it is taking energy from the system to form bonds. This takes away energy thus a negative energy.

Sean Reyes 1J
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Joined: Fri Sep 28, 2018 12:24 am

Re: Energy of Intermolecular Forces

Postby Sean Reyes 1J » Sat Nov 17, 2018 6:30 pm

Energy is required to form bonds. Because these are forming attractions with other molecules, this formation of bonds implies an exothermic reaction, which relates to a negative energy of the system

Catly Do 2E
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Re: Energy of Intermolecular Forces

Postby Catly Do 2E » Sat Nov 17, 2018 8:48 pm

It seems a little bit counterintuitive, but forming bonds requires energy. Creating a bond is bringing 2+ atoms into a more stable position. Thus, breaking the bond is where energy is absorbed whereas forming bonds is where energy is released.

Ariel Cheng 2I
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Joined: Fri Sep 28, 2018 12:29 am

Re: Energy of Intermolecular Forces

Postby Ariel Cheng 2I » Sun Nov 18, 2018 10:09 am

Breaking bonds generally requires an addition of energy. The opposite, forming bonds, is a release of energy which explains the negative number.

Arshia Ramesh 1G
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Re: Energy of Intermolecular Forces

Postby Arshia Ramesh 1G » Sun Nov 18, 2018 5:59 pm

you need energy to form bonds and energy is released when bonds are broken

Henry Dudley 1G
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Re: Energy of Intermolecular Forces

Postby Henry Dudley 1G » Fri Nov 23, 2018 12:11 am

Why do atoms form bonds if it requires energy?


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