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Diargon or the argon dimer is a molecule containing two argon atoms. Normally, this is only very weakly bound together by van der Waals forces (a van der Waals molecule ). However, in an excited state , or ionised state , the two atoms can be more tightly bound together, with significant spectral features.
Argon is the most abundant noble gas in Earth's crust, comprising 0.00015% of the crust. Nearly all argon in Earth's atmosphere is radiogenic argon-40, derived from the decay of potassium-40 in Earth's crust. In the universe, argon-36 is by far the most common argon isotope, as it is the most easily produced by stellar nucleosynthesis in ...
A large fraction of the chemical elements that occur naturally on the Earth's surface are essential to the structure and metabolism of living things. Four of these elements (hydrogen, carbon, nitrogen, and oxygen) are essential to every living thing and collectively make up 99% of the mass of protoplasm. [1]
The trend in the ionization energy of atoms is often used to demonstrate the periodic behavior of atoms with respect to the atomic number, as summarized by ordering atoms in Mendeleev's table. This is a valuable tool for establishing and understanding the ordering of electrons in atomic orbitals without going into the details of wave functions ...
About 99% of the Earth's atmosphere is composed of two species of diatomic molecules: nitrogen (78%) and oxygen (21%). The natural abundance of hydrogen (H 2) in the Earth's atmosphere is only of the order of parts per million, but H 2 is the most abundant diatomic molecule in the universe. The interstellar medium is dominated by hydrogen atoms.
Free nitrogen atoms easily react with most elements to form nitrides, and even when two free nitrogen atoms collide to produce an excited N 2 molecule, they may release so much energy on collision with even such stable molecules as carbon dioxide and water to cause homolytic fission into radicals such as CO and O or OH and H. Atomic nitrogen is ...
A period 2 element is one of the chemical elements in the second row (or period) of the periodic table of the chemical elements.The periodic table is laid out in rows to illustrate recurring (periodic) trends in the chemical behavior of the elements as their atomic number increases; a new row is started when chemical behavior begins to repeat, creating columns of elements with similar properties.
Pronounced "group five A" and "group five B"; "V" is the Roman numeral 5). In semiconductor physics, it is still usually called Group V. [3] The "five" ("V") in the historical names comes from the "pentavalency" of nitrogen, reflected by the stoichiometry of compounds such as N 2 O 5. They have also been called the pentels.