Thorium monosulphide, ThS cr

The melting temperature is not well-known. Samsonov and Popova [1957SAM/POP] and Shalek [1963SHA] have reported values of (2720 + 50) and 2608 K respectively. No value can be selected at this time. 

O Hare et al. [19750HA/ADE] studied the enthalpy of solution of a well-characterised sample of ThS by dissolution in 6.000 M HCl. The sample was the same as that used by Flotow et al. [1971FLO/OSB] for heat capacity measurements. More analytical details on the sample were given in [19750HA/ADE] - see Appendix A. The S/Th ratio of the monosulphide phase in the sample was calculated by the authors to be (1.029 + 0.019). 

There is some ambiguity in the reported processing, since the paper reports what is described as a measured enthalpy of reaction for a reaction which both explicitly and implicitly involves ThSi 029(cr). We therefore assume that it in fact refers to a measured value which has been adjusted for the presence of the impurities, although no mention is made in the paper as to the value assumed for Af//° (ThOS, cr, 298.15 K), which is not known experimentally. 

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