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Specialty Chemistry Forums => Other Sciences Question Forum => Topic started by: awhitney on May 05, 2006, 08:08:55 PM

Title: 2nd Law of Thermodynamics
Post by: awhitney on May 05, 2006, 08:08:55 PM
Hello, I am not sure which fourm I need to post this question in so I will try a few. 

In my Zoology class we are working through the chapter on Metabolism etc.  A question posed by my professor....

Why doesn't the heat absorption in an anabolic chemical reaction violate the 2nd Law of Thermodynamics?  In any chemical reaction for that matter...

                     6CO2 + 6H2O-------C6H12O6 + C6H12O6 +6O2

He states that the absorption of heat in any chemical reaction seems to violate the 2nd Law.  Can anyonte help explain this.
Thanks!
Title: Re: 2nd Law of Thermodynamics
Post by: tamim83 on May 05, 2006, 09:34:11 PM
Quote
He states that the absorption of heat in any chemical reaction seems to violate the 2nd Law.


Yeah, your professor is right, it Does seem to violate the second law of thermodynamics, the entropy of the system is less than zero which is unfavorable (the entropy of the universe is supposedly always increasing according to the second law).  However we also have to consider the entropy of the surroundings as well.  Somehow an anabolic processes results in an increase of the entropy of the system surroundings, i.e. energy or heat is relaesed to the surroundings by the system and this exchange is reversible.  I did not take a lot of bio so I am not sure what this would mean exactly, I am only speaking from a physical chemist's perspective.  Maybe further research would help you more, but I hope this helps you some.   ;)