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  2. Beryllium hydride - Wikipedia

    en.wikipedia.org/wiki/Beryllium_hydride

    Unlike the other group 2 metals, beryllium does not react with hydrogen. [3] Instead, BeH 2 is prepared from preformed beryllium(II) compounds. It was first synthesized in 1951 by treating dimethylberyllium, Be(CH 3) 2, with lithium aluminium hydride, LiAlH 4. [4] Purer BeH 2 forms from the pyrolysis of di-tert-butylberyllium, Be(C[CH 3] 3) 2 ...

  3. Chemical polarity - Wikipedia

    en.wikipedia.org/wiki/Chemical_polarity

    Polar molecules must contain one or more polar bonds due to a difference in electronegativity between the bonded atoms. Molecules containing polar bonds have no molecular polarity if the bond dipoles cancel each other out by symmetry. Polar molecules interact through dipole-dipole intermolecular forces and hydrogen bonds.

  4. Organoberyllium chemistry - Wikipedia

    en.wikipedia.org/wiki/Organoberyllium_chemistry

    Organoberyllium chemistry involves the synthesis and properties of organometallic compounds featuring the group 2 alkaline earth metal beryllium (Be). [2] The area remains less developed relative to the chemistry of other main-group elements, because Be compounds are toxic and few applications have been found. [3]

  5. Beryllium chloride - Wikipedia

    en.wikipedia.org/wiki/Beryllium_chloride

    Beryllium chloride is an inorganic compound with the formula BeCl 2. It is a colourless, hygroscopic solid that dissolves well in many polar solvents. Its properties are similar to those of aluminium chloride , due to beryllium 's diagonal relationship with aluminium .

  6. Ketene cycloaddition - Wikipedia

    en.wikipedia.org/wiki/Ketene_cycloaddition

    Ketene cycloadditions proceed by a concerted, [2+2] cycloaddition mechanism. Ketenes, unlike most alkenes, can align antarafacially with respect to other alkenes. Thus, the suprafacial- antarafacial geometry required for concerted, thermal [2+2] cycloaddition can be achieved in reactions of ketenes. [4]

  7. Helium dimer - Wikipedia

    en.wikipedia.org/wiki/Helium_dimer

    The helium dimer can be formed in small amounts when helium gas expands and cools as it passes through a nozzle in a gas beam. [2] Only the isotope 4 He can form molecules like this; 4 He 3 He and 3 He 3 He do not exist, as they do not have a stable bound state. [6] The amount of the dimer formed in the gas beam is of the order of one percent. [10]

  8. Tetrafluoroberyllate - Wikipedia

    en.wikipedia.org/wiki/Tetrafluoroberyllate

    H 2 BeF 4 is an acid that can be produced from Ag 2 BeF 4 and HCl. It only exists in aqueous solution. [11] Triglycine tetrafluoroberyllate (TGFB) is ferroelectric with a transition point of 70 °C. [26] The crystals can be formed by dissolving BeF 2 in water, adding HF and then glycine. When the solution is cooled triglycine ...

  9. Diagonal relationship - Wikipedia

    en.wikipedia.org/wiki/Diagonal_relationship

    For example, Li + is a small cation with a +1 charge and Mg 2+ is somewhat larger with a +2 charge, so the ionic potential of each of the two ions is roughly the same. It was revealed by an examination that the charge density of lithium is much closer to that of magnesium than to those of the other alkali metals. [ 3 ]