From the crude oxide so obtained (which contains lanthanum and didymium oxides) the cerium may be separated by conversion into its double sulphate on the addition of potassium sulphate, the sulphates of the cerium group being insoluble in a saturated solution of potassium sulphate.
The atomic weight of cerium has been determined by B.
Opium, cocaine or cerium oxalate.
The particular earth containing cerium was discovered by M.
In its salts, thorium is tetravalent, and in the periodic classification it occurs in the same sub-group as titanium, cerium and zirconium.
In its chemical affinities zirconium resembles titanium, cerium and thorium; it occurs in company with these elements, and is tetravalent in its more important salts.
Lanthanum sulphate, La2(S04)3.9H20, forms six-sided prisms, isomorphous with those of the corresponding cerium salt.
In its chemical relations, titanium is generally tetravalent, and occurs in the same sub-group of the periodic classification as zirconium, cerium and thorium.
He was the first to discover uranium, zirconium and titanium, and to characterize them as distinct elements, though he did not obtain any of them in the pure metallic state; and he elucidated the composition of numerous substances till then imperfectly known, including compounds of the then newly recognized elements: tellurium, strontium, cerium and chromium.
Cerous sulphide, Ce2S3, results on heating cerium with sulphur or cerium oxide in carbon bisulphide vapour.