Chromium(III) perchlorate explained

Chromium(III) perchlorate is an inorganic compound, a salt with the chemical formula Cr(ClO₄)₃. It's hexahydrate Cr(ClO₄)₃·6H₂O is a cyan solid that dissolves in water.

Preparation

Chromium perchlorate can prepared by reacting chromium(III) oxide or chromium(III) hydroxide with perchloric acid:

Cr₂O₃ + 6HClO₄ → 2Cr(ClO₄)₃ + 3H₂O

Hydrates

Chromium perchlorate has many hydrates, such as the hexahydrate Cr(ClO₄)₃·6H₂O^[1] and a nonahydrate Cr(ClO₄)₃·9H₂O.^[2] All of them are cyan substances that are soluble in water.

Related compounds

• Cr(ClO₄)₃ will react with NH₃ in suitable conditions to form an orange hexammine complex Cr(ClO₄)₃·6NH₃.^[3] Other compounds with the general formula Cr(ClO₄)₃(NH₃)_x are also known. When x = 3, this compound is red, when x = 4 or 5, it is orange.^[4] The hexammine complex will explode.^[4]
• Cr(ClO₄)₃ can also form complexes with N₂H₄, such as purple Cr(ClO₄)₃·2N₂H₄.^[5]
• Cr(ClO₄)₃ can also form complexes with urea (CO(NH₂)₂), such as Cr(ClO₄)₃·6CO(NH₂)₂ with a hexagonal structure.^[6]

Notes and References

1. Book: CRC Handbook of Chemistry and Physics. 97. William M. Haynes. CRC Press. 2016. 4–57. 9781498754293.
2. http://chromium.atomistry.com/chromium_perchlorate.html Chromium Perchlorate
3. Handbook of inorganic substances 2017 – Google Sách.
4. Book: Macintyre . Jane E. . Dictionary of Inorganic Compounds . 23 July 1992 . CRC Press . 978-0-412-30120-9 . 3278 . en.
5. Web site: http://chemistry-chemists.com/chemister/Neorganika/inorganic-hydrazine-derivatives-2014.pdf. . chemistry-chemists.com . https://web.archive.org/web/20200326015850/http://chemistry-chemists.com/chemister/Neorganika/inorganic-hydrazine-derivatives-2014.pdf . 2020-03-26.
6. Über Eisen-Harnstoffverbindungen. Chemisches Zentralblatt . 17 September 1913. 1035. 12. G. A.. Barbieri.