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Beryllium iodide can be prepared by reacting beryllium metal with elemental iodine at temperatures of 500 °C to 700 °C: [1]. Be + I 2 → BeI 2 When the oxidation is conducted on an ether suspension of elemental Be, one obtains colorless dietherate: [5]
Because these reactions are energetically favored, beryllium hydride has Lewis-acidic character. The reaction with lithium hydride (in which the hydride ion is the Lewis base), forms sequentially LiBeH 3 and Li 2 BeH 4. [3] The latter contains the tetrahydridoberyllate(2-) anion BeH 2− 4.
The Be 2+ cation, which is relevant to BeBr 2, is characterized by the highest known charge density (Z/r = 6.45), making it one of the hardest cations and a very strong Lewis acid. [ 3 ] Preparation and reactions
The characteristic properties of elemental metals and nonmetals are quite distinct, as shown in the table below. Metalloids, straddling the metal-nonmetal border , are mostly distinct from either, but in a few properties resemble one or the other, as shown in the shading of the metalloid column below and summarized in the small table at the top ...
In cosmology, dark energy is the name given to the source of the repelling influence that is accelerating the rate of expansion of the universe. Its precise nature is currently a mystery, although its effects can reasonably be modeled by assigning matter-like properties such as energy density and pressure to the vacuum itself. [66] [67]
Metallic hydrogen (recombination energy) 216 [2] Specific orbital energy of Low Earth orbit (approximate) 33.0: Beryllium + Oxygen: 23.9 [3] Lithium + Fluorine: 23.75 [citation needed] Octaazacubane potential explosive: 22.9 [4] Hydrogen + Oxygen: 13.4 [5] Gasoline + Oxygen –> Derived from Gasoline: 13.3 [citation needed] Dinitroacetylene ...
The energy associated to an electron is that of its orbital. The energy of a configuration is often approximated as the sum of the energy of each electron, neglecting the electron-electron interactions. The configuration that corresponds to the lowest electronic energy is called the ground state. Any other configuration is an excited state.
The elements have very similar properties: they are all shiny, silvery-white, somewhat reactive metals at standard temperature and pressure. [ 2 ] Together with helium , these elements have in common an outer s orbital which is full [ 2 ] [ 3 ] [ 4 ] —that is, this orbital contains its full complement of two electrons, which the alkaline ...