Alkali metal oxide

The alkali metals react with oxygen to form several different compounds: suboxides, oxides, peroxides, superoxides, and ozonides. They all react violently with water.

A sample of sodium peroxide.

Alkali metal suboxides

Structure of undecacaesium trioxide.
  • Hexarubidium monoxide (Rb6O) h
  • Nonarubidium dioxide (Rb9O2)
  • Caesium monoxide (CsO)
  • Tricaesium monoxide (Cs3O) is a dark green solid.
  • Tetracaesium monoxide (Cs4O)
  • Heptacaesium monoxide (Cs7O)
  • Tricaesium dioxide (Cs3O2)
  • Heptacaesium dioxide (Cs7O2)
  • Undecacaesium trioxide (Cs11O3)
  • Undecacaesium monorubidium trioxide (Cs11RbO3)
  • Undecacaesium dirubidium trioxide (Cs11Rb2O3)
  • Undecacaesium trirubidium trioxide (Cs11Rb3O3)

Alkali metal oxides

Crystal structure of rubidium oxide.
  • Lithium oxide (Li2O) is the lightest alkali metal oxide and a white solid. It melts at 1570 °C.
  • Sodium oxide (Na2O) is a white solid that melts at 1132 °C and decomposes at 1950 °C. It is a component of glass.
  • Potassium oxide (K2O) is a pale yellow solid that decomposes at 350 °C.
  • Rubidium oxide (Rb2O) is a yellow solid that melts at 500 °C.
  • Caesium oxide (Cs2O) is a yellow-orange solid that melts at 490 °C.

Alkali metal peroxides

Crystal structure of sodium peroxide.
  • Lithium peroxide (Li2O2) is a white solid that melts at 195 °C. It reacts with carbon dioxide to form lithium carbonate and oxygen.
  • Sodium peroxide (Na2O2) is a pale yellow solid that melts at 460 °C and decomposes at 657 °C.
  • Potassium peroxide (K2O2) is a yellow solid that melts at 490 °C.
  • Rubidium peroxide (Rb2O2) is produced when rubidium stands in air.
  • Caesium peroxide (Cs2O2) is produced by the decomposition of caesium oxide above 400 °C.

Alkali metal superoxides

Crystal structure of potassium superoxide.

Alkali metal ozonides

  • Lithium ozonide (LiO3) is a red solid which is produced from caesium ozonide via an ion-exchange process.
  • Sodium ozonide (NaO3) is a red solid which is produced from caesium ozonide via an ion-exchange process.[1]
  • Potassium ozonide (KO3) is a dark red solid which is produced when potassium is burned in ozone or exposed to air for years.
  • Rubidium ozonide (RbO3) is a dark red solid which is produced when rubidium is burned in ozone.
  • Caesium ozonide (CsO3) is a dark red solid which is produced when caesium is burned in ozone.[2]

References

  1. Klein, W.; Armbruster, K.; Jansen, M. (1998). "Synthesis and crystal structure determination of sodium ozonide". Chemical Communications (6): 707–708. doi:10.1039/a708570b.
  2. F. A. Cotton and G. Wilkinson "Advanced Inorganic Chemistry", 5th edition (1988), p.462
This article is issued from Wikipedia. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.