Comparative Data for Oxide Selenites

Th oxide selenites M202Se03 form by heating M2O2S in air. Th derivatograms show a single exothermic effect with a maximum at the following temperature t in °C  

The oxide selenites, being very unstable, undergo further weight loss due to the subsequent evolution of Se02, leaving M2O3 as the final product at 1200°C [2], see also [3]. Formation of M2O3 at 900°C is reported by [1]. 

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