Standard Energy Change of Formation
The standard Gibbs free energy of formation of a compound is the change of Gibbs free energy that accompanies the formation of 1 mole of that substance from its component elements, at their standard states (the most stable form of the element at 25 degrees Celsius and 100 kilopascals). Its symbol is ΔfG˚.
All elements in their standard states (oxygen gas, graphite, etc.) have 0 standard Gibbs free energy change of formation, as there is no change involved.
- ΔrG = ΔrG˚ + RT ln Qr; Qr is the reaction quotient.
At equilibrium, ΔrG = 0 and Qr = K so the equation becomes ΔrG˚ = −RT ln K; K is the equilibrium constant.
Read more about this topic: Gibbs Free Energy
Famous quotes containing the words standard, energy, change and/or formation:
“A dwarf who brings a standard along with him to measure his own sizetake my word, is a dwarf in more articles than one.”
—Laurence Sterne (17131768)
“Crime is naught but misdirected energy. So long as every institution of today, economic, political, social, and moral, conspires to misdirect human energy into wrong channels; so long as most people are out of place doing the things they hate to do, living a life they loathe to live, crime will be inevitable.”
—Emma Goldman (18691940)
“Where we come from in America no longer signifiesits where we go, and what we do when we get there, that tells us who we are.
The irony of the role of women in my business, and in so many other places, too, was that while we began by demanding that we be allowed to mimic the ways of men, we wound up knowing we would have to change those ways. Not only because those ways were not like ours, but because they simply did not work.”
—Anna Quindlen (b. 1952)
“... the mass migrations now habitual in our nation are disastrous to the family and to the formation of individual character. It is impossible to create a stable society if something like a third of our people are constantly moving about. We cannot grow fine human beings, any more than we can grow fine trees, if they are constantly torn up by the roots and transplanted ...”
—Agnes E. Meyer (18871970)