Hydrogen gallium

A mixture of gallium/hydrogen peroxide in 30% hydrochloric acid detonates if chilled insufficiently. 

Lithium tetrahydridogallate, which was first prepared by Finholt, Bond, and Schlesinger,1 is a very useful starting material for the preparation of gallium hydride derivatives.2-3 The present synthesis is based on an adaptation of the original preparation.1-4 Since gallium-hydrogen bonds are susceptible to hydrolysis, it is necessary to perform the preparation in the absence of air. The procedure described is based on the use of Schlenk-type inert-atmosphere techniques. 

Collins SE, Baltanas ML, Fierro JLG, Bonivardi AL (2002). Gallium-hydrogen bond formation on gallium and palladium-gallium silica-supported catalysts. J Catal, 211, 252... 

B1.29.6 HIGH-PRESSURE FORMS OF FAMILIAR OR USEFUL MATERIALS DIAMOND, FLUID METALLIC HYDROGEN, METALLIC OXYGEN, IONIC CARBON DIOXIDE, GALLIUM NITRIDE... 

Boron, being chemically a non-metal, is resistant to attack by nonoxidising acids but the other members of the group react as typical metals and evolve hydrogen. Aluminium, gallium and indium are oxidised to the + 3 oxidation state, the simplified equation being... 

If trimethyl gallium is mixed widi arsine, ASH3, the hydrogen atoms released by the dissociation of this gas react with the methyl radicals released from gallium trimediyl according to the equation... 

Aluminium B a 5 o B B < I Antimony a < Barium B a 1 3 Bismuth I Boron Cadmium 1 Caesium Calcium 1 Cerium Chloride, Chlorine [ Chromium X) o o C o a Gallium I Germanium Gold 1 Hafnium Hydrogen sulphide B a 5 a B a 5 a o 1 Lanthanons Lead f Lithium 1 Magnesium f Manganese Mercury Molybdenum... 

Dining dissolution for analysis of 1 -9 g samples of gallium in cone, hydrochloric acid containing small portions of 30% hydrogen peroxide solution, cooling may be necessary to prevent development of explosively violent reactions at higher temperatures. 

The gallium modified zeolites were activated by two successive reduction-oxidation cycles, respectively with hydrogen and air, which, according to the literature [3], lead the catalyst to its most active form. 

Figure 1. - Pulse reaction studies results. Left Propane pmol converted per gram of catalyst. Right Hydrogen pmol produced per gram of catalyst. Squares - catalyst with 2 wt%. of gallium. Circles - catalyst with 3 wt.% of gallium.

The pulse experiments demonstrated that active sites for propane dehydrogenation are formed upon exposure of the oxide form of gallium modified ZSM-5 to propane itself. A constant 1 1 ratio of hydrogen produced to propane consumed is attained after a number of pulses with little propene formation, which suggests that, after propane dehydrogenation to propane, aromatization proceeds through hydrogen transfer reactions. 

Note that only in the case of gallium, with a deep subcooling, the reference is linked to the melting point instead that to the freezing point. a All substances (except 3 He) are of natural isotopic composition. e-H2 is hydrogen at the equilibrium concenttation of the ortho and para molecular forms. 

It is worth noticing that, besides silicon, other donors in gallium or arsenic sites can be neutralized as well by hydrogen in GaAs (Pearton et al., 1986). An interesting feature is the dissociation energy trend of... 

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