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Re: [Phys-L] Energy & Bonds



This may have _historically_ been the case, but my conversations with
biologist indicate that this has been corrected in the past ten years.
Not sure about all the bio books, but the internet empowers students
to question "authoritative" textbooks, which is a good thing -- keeps
everyone learning.

Dr. Roy Jensen
(==========)-----------------------------------------¤
Lecturer, Chemistry
E5-33F, University of Alberta
780.248.1808




On Tue, 12 Nov 2013 17:09:59 -0600, you wrote:

YES, YES, YES. I have repeately pointed out that it the released energy
comes from hydration, forming new bonds. This is always ignored in bio
books. But if you read the Wikipedia account it gets it right! The bio
books do more than gloss. They state that breaking the bonds releases
energy, but many books will say that this only true for breaking the bonds
in the Krebs cycle. In other words they are completely wrong. This also is
done in physical science books.

John M. Clement
Houston, TX


So here's the thing... Ultimately, energy is not stored in a
bond. You can often, however, ADD energy, break that bond,
form a NEW bond, and end up with a NET release in energy.
That (extra) energy comes from the field between the original
atoms and NEW atoms in their vicinity... BUT... that 'field
energy' can only be accessed by breaking the original bonds.
Going back to ATP, you have to break those initial bonds,
absorbing energy, and THEN new, stronger bonds form releasing
more energy than was initially added.

Biology typically glosses over the intermediate steps and
leaves kids with a completely incorrect concept. As a
result, the topic of bonding in chemistry is one of the most
confusing they ever face.



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