[audio:https://www.podtrac.com/pts/redirect.mp3/traffic.libsyn.com/sciencefriday/scifri201112234.mp3]Cooking crystal meth is just “basic chemistry” for Walter White, the fictional chemistry teacher and anti-hero of the TV drama “Breaking Bad.” Organic chemist Donna Nelson serves as science adviser to the show; she explains how the series’ writers work to get the science right.