Add time:08/02/2019         Source:sciencedirect.com

The thermal decomposition of (YbO)2Se(s) was studied over the temperature range 1753–1997 K by the Knudsen effusion weight loss technique. The decomposition leads to a gas phase containing ytterbium and selenium with a molar ratio of 2:3 and to a residue of Yb2O3(s). Using literature and estimated enthalpy and entropy data for the gaseous species Yb, Se, YbSe and Se2, it could be established from the rates of effusion that the principal decomposition reaction is (YbO)2Se(s) → 23Yb203(s) + 23Yb(g) + Se(g)The following second-law (index II) and third-law (index III) enthalpies and entropies are found for this reaction: ΔH298o(II) = 720.8 ± 33.2 kJ mol−1ΔS298o(II) = 230.6 ± 18.8 J mol−1 K−1ΔH298o(III) = 711.4 ± 28.0 kJ mol−1ΔS298o(III) = 225.7 J mol−1 K−1A value of − 1594 ± 33 kJ mol−1 is derived for ΔHf298o ((YbO)2Se(s)). The feasibility of this value is discussed in view of the significant decrease of the formula volume accompanying the formation of (YbO)2Se from Yb2O3 and Yb2Se3.

We also recommend Trading Suppliers and Manufacturers of YTTERBIUM SELENIDE (cas 12039-54-2). Pls Click Website Link as below: cas 12039-54-2 suppliers