Last week I wrote about how to construct a simple sheet metal “bridge,” which, in combination with an ice cube bucket and a jelly jar, makes an effective pneumatic trough for collecting gas samples over water. This week I’m going to show you how to use this apparatus to generate and collect pure oxygen, and how to use that oxygen to observe the brilliant blue flame of sulfur oxidation.Continue Reading
Harvard’s George M. Whitesides is arguably the world’s most significant chemist. How arguably? Whitesides has the highest Hirsch index of any living chemist in the world. The Hirsch or h-index is a kind of weighted score based on a numerical analysis of a scientist’s published work which factors in both the number of papers and the number of citations those papers receive by other authors.
Back in October of 2008, Whitesides published a paper in the Royal Society of Chemistry’s journal Lab on a Chip that describes a technique for separating blood plasma for use in various immunoassays using a piece of plastic tubing taped to an eggbeater. The method can replace a $400 bench centrifuge for many purposes.Continue Reading