Noble gas compound Noble gas compound Noble gas compounds are chemical compounds that include an element from the noble gases, group 18 of the periodic table. Although the noble gases are generally unreactive elements, many such compounds have been observed, particularly involving the element xenon. From the standpoint of chemistry, the noble gases may be divided into two groups: the relatively reactive krypton (ionisation energy 14.0 eV), xenon (12.1 eV), and radon (10.7 eV) on one side, and the very unreactive argon (15.8 eV), neon (21.6 eV), and helium (24.6 eV) on the other. Consistent with this classification, Kr, Xe, and Rn form
An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction "An Experimental Enquiry Concerning the Source of the Heat which is Excited by Friction" (1798), which was published in the "Philosophical Transactions of the Royal Society", is a scientific paper by Benjamin Thompson, Count Rumford that provided a substantial challenge to established theories of heat and began the 19th century revolution in thermodynamics. Rumford was an opponent of the caloric theory of heat which held that heat was a fluid that could be neither created nor destroyed. He had further developed the view that all gases