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Re: [Phys-L] Energy & Bonds



The qs have opposite signs. The potential is negative. The smaller r, the lower (more negative) the value of the potential energy.

-----Original Message-----
From: Phys-l [mailto:phys-l-bounces@phys-l.org] On Behalf Of Paul Lulai
Sent: Tuesday, November 12, 2013 1:21 PM
To: Phys-L@Phys-L.org
Subject: Re: [Phys-L] Energy & Bonds

How do I reconcile this with U=kqq/r ?
Isn't r getting smaller as they approach and bond? Then U is getting larger.

What is wrong with my model here?

-----Original Message-----
From: Phys-l [mailto:phys-l-bounces@phys-l.org] On Behalf Of Dr Keith S
Taber
Sent: Tuesday, November 12, 2013 11:56 AM
To: Phys-L@Phys-L.org
Subject: Re: [Phys-L] Energy & Bonds

Hi Paul

In your terms

The products are more bound because they must be more bound and have
LESS potential energy

i.e. they require more energy to disrupt the bonds as there is stronger
binding

Best wishes

Keith


On 12/11/2013 15:01, Paul Lulai wrote:
Hi.
I am more aware of my conceptual shortcomings after the conversation
about energy, reactions, and misconceptions.
I would appreciate clarification from the group on:
How do we reconcile the traditional Exothermic & Endothermic graphs of
Energy vs reaction process with the fact that the products must be more
bound and have greater potential energy? Typically the endo / exo graphs
show (for an exothermic reaction) that the reactants have more energy than
the products.

I may have more follow up questions.
Thanks.
Paul.
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--


Dr. Keith S. Taber
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University Reader in Science Education University of Cambridge Faculty of
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_______________________________________________
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_______________________________________________
Forum for Physics Educators
Phys-l@phys-l.org
http://www.phys-l.org/mailman/listinfo/phys-l