(source: https://www.rsc.org/periodic-table/element/100/fermium)

Fermium can be separated from einsteinium and californium  by reducing it with metallic magnesium in hydrochloric acid-acetic acid followed by co-crystallization with samarium dichloride: Method For Recovering Fermium (1993).

To obtain fermium in the divalent state a hydrochloric acid-ethanol water solution of trivalent fermium is treated with samarium trichloride and metallic magnesium: Method Of Preparing Fermium In A Bivalent State (1979)).


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