Sublimation, heat metals

Carbon dioxide, COj. Sublimes — 78 5 C. A colourless gas at room temperature, occurs naturally and plays an important part in animal and plant respiration. Produced by the complete combustion of carbon-containing materials (industrially from flue gases and from synthesis gas used in ammonia production) and by heating metal carbonates or by... 

Gasless Mixture 668/Mn Mn 10, Cu 30, Si 30 Pb02 30%. Pressure on heating of this mixture was developed by sublimation of metals Ref W.A. Show, Development of an Incendiary Pellet , Tech Command Army Chem Center, Md Kept TCR-59 (May 1950)... 

Heat of sublimation of metal (kcal per gram-atom) 25.9 19 8... 

Osmium Tetrachloride, OsCl4, is obtained as a reddish brown sublimate when metallic osmium is heated in chlorine (Berzelius) between 650° and 700° C.1... 

Latent heats of evaporation and sublimation of metals have been calculated from the vapour pressures by the Clapeyron-Clausius equation ( 7.VIII L). 

The values for the heats of sublimation of metals given in Table CXXXIX although only approximate, bring out some important relationships. In... 

Table CXXXIX. Heats of Sublimation of Metals (kcals)...

The usual commercial grade of HC1 is a chlorination by-product, and the chlorinated hydrocarbons therein contribute a significant carbide impurity in the trichloride through their reaction with the heated metal. Subsequent removal of this appears to require one extra sublimation. However, high purity electronic-grade HC1 (available from several gas suppliers) greatly reduces contamination from traces of the chlorocarbons, 02, N2, and H20 which are present in the usual grade of HC1. 

Sublimation of metallic elements from rock or ore samples requires high temperatures. The equipment used is based upon silica furnace tubes in order to withstand the necessary conditions. The silica tube is heated in a furnace and the sublimate condenses either on a cool part of the tube or on a cooled surface immediately after leaving the tube. 

Heat of Fusion For Elements and Inorganic Compounds Heats of Sublimation of Metals and Their Oxides Key to Tables of Thermodynamic Coefficients Thermodynamic Coefficients for Selected Elements Thermodynamic Coefficients for Oxides Entropy of the Elements... 

Their procedure entailed heating stoichiometric quantities of sublimed Dy metal and Ij at 680°C for 20 days. 

Those components with small sublimation heats can segregate on surfaces because the surface tensions of metals are connected with its sublimation heats. There are no such connections between the surface tension and the sublimation heats on the surface of oxides. 

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