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How is the entropy of mixing related to chemical reactions in solution?

For a reaction of ideal gases, such as, say, aA+bB-->cC+dD, the $\Delta G_r$ in your equation is the change in Gibbs free energy in going at constant temperature T from a moles of pure A and b ...
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2 votes

How is the entropy of mixing related to chemical reactions in solution?

So, I am gonna use the most basic definition of entropy - the statistic one S = kB ln $\Omega$ $\Omega$ is the total number of microstates possible. In your case, different microstates can be formed ...
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Is the entropy change positive or negative in this reaction?

But how is dS positive? How can it be explained theoretically? The reaction entropy rules usually taught first are about the physical state of the pure substances. If you go from a condensed state (...
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1 vote

Spontaneity criterion for phase transformations and chemical reactions

Spontaneity is simply a system not at equilibrium (this is regardless of direction) with a possible mechanism to reach equilibrium. Before getting upset note that reactions involving only standard ...
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Spontaneity criterion for phase transformations and chemical reactions

Enthalpy $H$ is not a valid criterion for spontaneous reactions. Spontaneous reactions may be exothermic or endothermic. The famous reaction of $\ce{NaHCO3 + HCl}$ is endothermic, but it is ...
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3 votes

Why is rapid expansion/compression reversible?

The process described in the theoretical Otto cycle is idealized, it is performed so quickly that there is no opportunity for heat to be exchanged (and is therefore adiabatic). In essence any process ...
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