Chemical elements that condense (or Conversion of liquids into gases, usually by heating them.) at relatively low temperatures. The opposite of Substances which have a tendency to enter the gas phase relatively easily (by evaporation, addition of heat, etc.). is refractory. Volatile elements can be divided into moderately volatile (Tc = 1230–640 K) and highly volatile (Tc < 640 K). The moderately volatile lithophile elements are: Mn, P, Na, B ,Rb, K, F, Zn. The moderately volatile siderophile and chalcophile elements are: The astronomical unit for length is described as the "mean" distance (average of aphelion and perihelion distances) between the Earth and the Sun. Though most references state the value for 1 AU to be approximately 150 million kilometers, the currently accepted precise value for the AU is 149,597,870.66 km. The, Cu, Ag, Ga, Sb, Ge, Sn, Se, Te, and S. The highly volatile lithophile and atmophile elements are Cl, Br, I, Cs, Tl, H, C, N, O, He, Ne, Ar, Kr, and Xe. The highly volatile siderophile and chalcophile elements are: In, Bi, Pb, and Hg.
Volatile elements are defined as those that condense at relatively low temperature (e.g., < 1100 K) from the putative solar gas while refractory, non-volatile elements condense at higher temperatures.
Such elements include sodium, indium, gold, mercury, and the Element occurring in the right-most column of the periodic table; also called "inert" gases. In these gases, the outer electron shell is completely filled, making them very unreactive. (e.g., Helium (He) Second lightest and second most abundant element (after Hydrogen) in the universe. The most abundant isotope is 4He (99.9998%), 3He is very rare. Helium comprises ~8% of the atoms (25% of the mass) of all directly observed matter in the universe. Helium is produced by hydrogen burning inside, neon, Noble gas represented by the atomic symbol Ar, that has Z = 18, and an atomic weight of 39.948. It is colorless, odorless, and very inert gas, comprising ~1 % of the Earth's atmosphere., krypton, xenon).