<p>Does anyone know what edition book for 21L by Chang they are using this semester (which did u use)? I looked on the bookstore website, but the ISBN number doesn't work because the package was made especially for Duke. (and since we prob. won't be using ARIS software or whatever, I don't want it). Is it the 8th edition? And for EGR 53, is the int'l edition book the exact same as the US book?</p>
<p>21 L is the 9th edition, but my main question is with the Chemistry Loose-Leaf Package, is it or is it not optional? since under section 001 its required but under section 002 its optional, but yet its the same teacher. And u can find the 21L with the ARIS software but you need the sol. manual</p>
<p>I'm so confused. We need the solution manual but not the ARIS software? I really would like to buy my chem books beforehand, but this is just too complicated.</p>
<p>The chem package stuff just got too complicated for me so I just bought a used one from Duke. It's the only textbook I'm buying from Duke.</p>
<p>If I remember correctly, the "loose leaf" package is an alternate version of the textbook.</p>
<p>And I don't know what the deal is with the software.</p>
<p>Yes. The international edition for EGR 53 is exactly the same as the US book, except it has a soft cover instead of hard cover.</p>