Beryllium specific heat

Chemical Designations - Synonyms Beryllium Sulfate Tetrahydrate Chemical Formula BeS04 4H20. Observable Characteristics - Physical State (as normally shipped) Solid Color White Odor None. Physical and Chemical Properties - Physical State at 15 G and 1 atm. Solid Molecular Weight 177.14 Boiling Point at I atm. Not pertinent (decomposes) Freezing Point Not pertinent Critical Temperature Not pertinent Critical Pressure Not pertinent Specific Gravity 1.71 at 11°C (solid) Vapor (Gas) Density Not pertinent Ratio of Specific Heats of Vapor (Gas) Not pertinent Latera Heat of Vaporization Not pertinent Heat of Combustion Not pertinent Heat of Decomposition Not pertinent. 

In 1885 the issue was finally conclusively settled in favor of Mendeleev by measurements of the specific heat of beryllium at elevated temperatures. These experiments pointed to an atomic weight of 9.0, in reasonable agreement with Dulong and Petit s law and supported the di-valency of the element (Humpidge, 1885). Above all else, Mendeleev persisted in the belief that beryllium lies in group II because of his faith in the validity of the periodic law, which he believed was essentially a feature of the transcendental elements. All else was rationalized around this central tenet. 

In this study, thermal diffusivity and specific heat of Be/Cu mixture sintered compacts were measured by laser flash method, then thermal conductivity was obtained from calculation of those measured values. And thermal expansion coefficient was measured by laser interferometry method. These thermophysical properties were measured in order to characterized those compacts as interlayer between beryllium and copper alloy used in the plasma facing components. The obtained results are as follows. 

The specific heat at ordinary temperatures is abnormal as in the case of boron, carbon and silicon, but Humpidge (1885 i, 1886 i) has shown that between 400° and 500° it remains practically constant at about 0.62. The matter was one of long controversy and the low results obtained by Nilson and Fetters-son (1878 3) and others was the chief cause of the belief in the trivalency of beryllium. According to Humpidge (1885 i and 6, 1886 i) the relation between specific heat and temperatures can be expressed by the empirical formula ... 

Anhydrous Beryllium Sulphate, BeSO. —Nilson and Petters-son (1880 9) prepared a product very close to the composition BeSOi by heating the dihydrate at 250 . The sulphate so prer pared had a specific gravity=2.443 and a specific heat=o.i978. Lcbeaii (1896 6, 1899 ii) prepared the anhydrous sulphate by the action of strong sulphuric add on the oxide and evaporation of the excess of acid. Parsons (1904 10) states that while... 

Determined specific heat as 4453 from a 94 per cent, metal made by action of Na on BeClj. Speaks of the possibility of electrolyzing double fluoride of K and Be, but says material is very impure from fluorine attacking containing vessel. Gives many properties of Be and BeO not consistent with those of later investigators. Main study was evidently on specific Tieat, which being obtained at low temperatures, lead him to the belief in trivalent beryllium. 

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