D2O.
This is a small ampule of high-purity (99.96%) heavy water. The "purity" of the sample is listed as 20% because that's the weight-percent of hydrogen (deuterium actually) in heavy water.
This is a spare from the beautiful periodic table display that Max Whitby and I recently installed at DePauw University. Source:Max Whitby of RGB Contributor:Max Whitby of RGB Acquired:1 November, 2003 Text Updated:11 August, 2007 Price: Donated Size: 2" Purity: 20%
