In any spontaneous process entropy increases.In biological systems disordered elements are converted into highly ordered tissues etc(-ve entropy change) which make up living organisms. But, it requires energy from the sun(ultimately). So,does that mean all processes that consume energy from outside result in negative entropy change? Endothermic reactions consume energy in the form of heat from outside so, is all endothermic reactions causing the entropy to decrease?
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asked Oct 14, 2013 at 13:44
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Entropy increases in a spontaneous evolution of an isolated system… other than that, there is no general law on the evolution of entropy.
does that mean all processes that consume energy from outside result in negative entropy change?
No. When you heat a solid, it increases its entropy.
endothermic reactions causing the entropy to decrease?
Endothermic reactions which cause entropy to decrease have both ∆H positive and ∆S negative, so they will have a positive ∆G, i.e. their are not thermodynamically favorable.
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$\begingroup$ So, is there a general answer for-In which types of reactions does entropy increase/decrease? $\endgroup$ Commented Oct 14, 2013 at 15:43
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$\begingroup$ @RajathKrishnaR I have edited my post yesterday to reply to your question (at the top) $\endgroup$– F'xCommented Oct 15, 2013 at 15:29