Holmium(III) nitrate

Holmium (III) nitrate is an inorganic compound, a salt of holmium and nitric acid with the chemical formula Ho(NO₃)₃. The compound forms yellowish crystals, dissolves in water, also forms crystalline hydrates.

Synthesis

Anhydrous salt is obtained by the action of nitrogen dioxide on holmium(III) oxide:

${\displaystyle {\mathsf {2Ho_{2}O_{3} 9N_{2}O_{4}\ {\xrightarrow {150^{o}C}}\ 4Ho(NO_{3})_{3} 6NO}}}$

Effect of nitrogen dioxide on metallic holmium:

${\displaystyle {\mathsf {Ho 3N_{2}O_{4}\ {\xrightarrow {200^{o}C}}\ Ho(NO_{3})_{3} 3NO}}}$

Reaction of holmium hydroxide and nitric acid:

${\displaystyle {\mathsf {Ho(OH)_{3} 3NHO_{3}\ \xrightarrow {150^{o}C} \ Ho(NO_{3})_{3} 3H_{2}O}}}$

Physical properties

Holmium(III) nitrate forms yellowish crystals.

Forms a crystalline hydrate of the composition Ho(NO₃)₃•5H₂O.

Soluble in water and ethanol.

Chemical properties

Hydrated holmitic nitrate thermally decomposes to form HoONO
₃ and decomposes to holmium oxide upon subsequent heating.

Application

The compound is used for the production of ceramics and glass.

Also used to produce metallic holmium and as a chemical reagent.

References