Russ. Chem. Rev. 1968, 37(9),701中说europium(II) hydroxide is appreciably soluble in an alkaline solution。碱性环境极易溶解。 Concise encyclopedia chemistry(1994年出版)P394 也说"europium (II) sulfate is scarcely soluble in water, while europium (II) hydroxide dissolves readily" 。极易溶解,