Inductively coupled plasma mass spectrometry argon ions. Making the plasma from argon, instead of other gases, has several advantages. First, argon is abundant (in the atmosphere, as a result of the radioactive decay of potassium) and therefore cheaper than other noble gases. Argon also has a higher first ionization potential than all other elements except He, F, and Ne. Because of this high ionization energy, the reaction (Ar + e → Ar) is more energetically favorable than the reaction (M + e → M). This ensures that the sample remains ionized (as M) so that the mass spectrometer can detect it. Argon can be purchased
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