I am currently selling a used copy of "Principles of CHEMISTRY A Molecular Approach" (Custom Edition for Stanford University). This is this years currently used textbook for chem 31a/b. New the book cost 153$ (just checked) and used 113$, but i just went to the book store and there are ONLY new textbooks available. I am willing to part ways with this wonderful volume of knowledge for the low LOW price of 90$ cash money, which will save you 56$ if you buy it new or 23$ if you buy it cheap, but i will reiterate THERE ARE NO USED COPIES IN THE BOOKSTORE. If this post is still up that means the book hasn't been sold yet and it's first come first serve.