Noble gas to be retained. Neon, argon, krypton, and xenon also form clathrate hydrates, where the noble gas is trapped in ice. Noble gases can form endohedral fullerene compounds, in which the noble gas atom is trapped inside a fullerene molecule. In 1993, it was discovered that when , a spherical molecule consisting of 60 carbon atoms, is exposed to noble gases at high pressure, complexes such as can be formed (the "@" notation indicates He is contained inside but not covalently bound to it). As of 2008, endohedral complexes with helium, neon, argon, krypton, and xenon have been obtained. These compounds
Copia: Foundations of the Abundant Style book was immensely popular in England and in Europe, at least 85 editions of the book were printed in Erasmus' own lifetime, and countless more after that. Erasmus made three separate revisions to the original text, adding chapters each time. The original 1512 edition contained 153 chapters, which swelled to 206 in the final version that Erasmus completed before his death. Copia: Foundations of the Abundant Style Copia: Foundations of the Abundant Style () is a rhetoric textbook written by Dutch humanist Desiderius Erasmus, and first published in 1512. It was a best-seller widely used for teaching how to rewrite