Abundance of the chemical elements stars. Lithium, beryllium and boron are rare because although they are produced by nuclear fusion, they are then destroyed by other reactions in the stars. The elements from carbon to iron are relatively more common in the universe because of the ease of making them in supernova nucleosynthesis. Elements of higher atomic number than iron (element 26) become progressively more rare in the universe, because they increasingly absorb stellar energy in being produced. Elements with even atomic numbers are generally more common than their neighbors in the periodic table, also due to favorable energetics of formation. The abundance of elements
Mendeleev's predicted elements a systematic element name based on the atomic number of the element as the provisional name, instead of being based on its position in the periodic table as these prefixes require. The four predicted elements lighter than the rare-earth elements, "eka-boron" ("Eb"), "eka-aluminium" ("Ea" or "El",), "eka-manganese" ("Em"), and "eka-silicon" ("Es"), proved to be good predictors of the properties of scandium, gallium, technetium, and germanium respectively, which fill the spot in the periodic table assigned by Mendeleev. The names were written by Mendeleev as экаборъ, экаалюминій, экамарганецъ, and экасилицій respectively, following the pre-1917 Russian orthography. Initial versions of the periodic