Samarium. 31 



B. The yellow salt SmoO,, öV^O, + 24H2O. 



0.3833 gram lost at 100° 0.0781 gram and at a red heat 0.0217 gram 

 H2O in addition. The anhydrous salt was treated as described above 

 and gave 0.0794 gram SmjOa fi"d 0.2041 gram V2O5. 



99.99 1690 100.00 



Spec. Grav: 



0.5851 gram, large crystals, temp. 17*'.5, sp. Gr. 2.628 

 0.5852 » » » » 17".8, » » 2.620 



Mean of both determinations: 2,624. 

 Molecular volume: 1690/2.624 = 644. 



Molybdate of samarium 



Sm2 3Mo04. 



A neutral solution of the nitrate of samarium gives with an excess 

 of molybdate of ammonia (6NH4, Mo, O24) a voluminous white precipitate 

 which, if warmed, is changed into a heavy, granular, non crystalline 

 powder. Much samarium remains in solution. As the salt was amor- 

 phous it was not subjected to analysis. In order to obtain crystallised 

 molybdate, calculated quantities of molybdic acid and oxide of sama- 

 rium (SmgOg : 3M0O3) were mixed with pure chloride of sodium and 

 heated in a large platinum-crucible for some hours to bright red heat. 

 After cooling the mass was treated with water, which left l:o heavy, 

 violet-coloured, very brillant crystals 2:o fine microscopic needles and 

 3:o brillant scales, resembling boracic acid, insoluble in ammonia and 

 slowly soluble in hydrochloric acid; of 3 only a small quantity, insuffi- 

 cient for analysis was obtained. The two other sets of molybdates could 

 be pretty completely separated by elutriation. The heavy crystals were 

 neutral molybdate of samarium and the light needles (2) a molybdate of 

 samarium and sodiimi. 



