(i) Explain why the freshman criterion for sponteneity: G=H-TS < 0 is just a statement of the second law of thermodynamics (that the entropy of the universe always increases).

Question

Now apply this concept to some ice cubes sitting in a mojito, where the chemical process of interest is: H2O(s)  H2O (l)

ii) Are S and H for the system positive or negative? Explain why
iii) Explain what the relative magnitude of H/T to S is (i.e. are the terms larger, smaller or equal?) at 260K and 340K.
iv) 10g of ethanol at 290K are mixed with 10g of ethanol at 310K in an insulated beaker. Show that heat transfer from the warmer ethanol is a spontaneous process

Answer 1

Look up the second law of thermodynamics, memorize it, and apply it to (i).
(ii) What does the delta G tall you?
(iii) Use delta G = delta H - Tdelta S