Helium Helium Helium (from ) is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas, the first in the noble gas group in the periodic table. Its boiling point is the lowest among all the elements. After hydrogen, helium is the second lightest and second most abundant element in the observable universe, being present at about 24% of the total elemental mass, which is more than 12 times the mass of all the heavier elements combined. Its abundance is similar to this figure in the Sun and in Jupiter. This
Extinct isotopes of superheavy elements the theoretical progenitor of CCF Xe to be on the order of 10 years. A later attempt at characterization of the progenitor in 1975 by Edward Anders, a professor of chemistry at the University of Chicago, and colleague John Larimer suggested a heat of vaporization of 54 kJ/mol and a boiling point of 2500K for the element and, based on estimated accretion temperatures, they also proposed elements 111 and 115 (today named roentgenium and moscovium) as the most likely candidates assuming the element condensed in pure form. Anders went on to study samples of the Allende meteorite, the largest carbonaceous