Actinium(III) hydroxide

Actinium(III) hydroxide is a white radioactive solid with the chemical formula of Ac(OH)₃.

Actinium(III) hydroxide

Names
Other names Actinium hydroxide
Identifiers
CAS Number	12249-30-8 Y
3D model (JSmol)	Interactive image
InChI InChI=1S/Ac.3H2O/h;3*1H2/q+3;;;/p-3 Key: FXNGTWJQBRAZDM-UHFFFAOYSA-K
SMILES [Ac+3].[OH-].[OH-].[OH-]
Properties
Chemical formula	Ac(OH)3
Appearance	white solid
Solubility in water	0.021 in water (20 °C)
Related compounds
Other anions	actinium(III) oxide
Other cations	scandium(III) hydroxide yttrium(III) hydroxide lanthanum(III) hydroxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation

Actinium(III) hydroxide may be formed from soluble actinium salts and alkalis or ammonia water, and the resulting gel is precipitated as the product:^[1]

Ac³⁺ + 3 OH⁻ → Ac(OH)₃↓

Its solubility is slightly greater than that of lanthanum hydroxide, but it is still insoluble in water.

Chemical properties

Actinium(III) hydroxide is an alkaline hydroxide, it can react with acids to obtain actinium salts:^[1]

Ac(OH)₃ + 3 HNO₃ → Ac(NO₃)₃ + 3 H₂O