Which gaseous element has the lowest melting and boiling points of all the elements?
Period 1 element (He) is a colorless, odorless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas series in the periodic table and whose atomic number is 2. Its boiling and melting points are the lowest among the elements and it exists only as a gas except in extreme conditions. Helium was discovered in 1868 by French astronomer Pierre Janssen, who first detected the substance as an unknown yellow spectral line signature in light from a solar eclipse. In 1903, large reserves of helium were found in the natural gas fields of the United States, which is by far the largest
Critical points of the elements (data page) Critical points of the elements (data page) David R. Lide (ed), "CRC Handbook of Chemistry and Physics, 85th Edition", online version. CRC Press. Boca Raton, Florida, 2003; Section 6, Fluid Properties; Critical Constants. Also agrees with Celsius values from Section 4: Properties of the Elements and Inorganic Compounds, Melting, Boiling, Triple, and Critical Point Temperatures of the Elements J.A. Dean (ed), "Lange's Handbook of Chemistry" (15th Edition), McGraw-Hill, 1999; Section 6; Table 6.5 Critical Properties National Physical Laboratory, "Kaye and Laby Tables of Physical and Chemical Constants"; D. Ambrose, M.B. Ewing, M.L. McGlashan, Critical constants and second virial coefficients of