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PiRsq
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Homework Statement
A. Explain the need for Gibbs Free Energy equation.
B. Explain what it means when:
[tex]\Delta G <0[/tex] [tex]\Delta G >0[/tex] [tex]\Delta G =0[/tex]
Homework Equations
[tex]\Delta G= \Delta H-T \Delta S[/tex]
The Attempt at a Solution
A. Gibbs eqn comes from the need to calculate the entropy of the universe, which is the sum of entropy of system + entropy of surroundings. The need for the Gibbs eqn is because of the problem arising with calculating the entropy of surroundings as there are uncountable entropy changes that take place when heat is released into the surroundings. Gibbs eqn deals with this by eliminating the entropy of surroundings and replacing with an eqn that only has entropy of system on the right side of the eqn.
B. I am confused over here:
If [tex]\Delta G<0[/tex] then the process is spontaneous. This means[tex]\Delta H<0[/tex] and [tex]\Delta S>0[/tex] But how can the system release heat and also have an increase its entropy?