Oxygen Fluorides

(redirected from Fluorine oxide)

Oxygen Fluorides

 

compounds that contain an O—F bond, such as oxygen difluoride, OF2, dioxygen difluoride, O2F2, fluorine nitrate, FNO3, and fluorine perchlorate FC1O4. Fluorine forms with oxygen in a glow discharge a mixture of stable F—O—O radicals and fluorine atoms; condensation of the mixture at – 196°C yields higher oxygen fluorides, such as O2F2 and O3F2, which are stable only at low temperatures. All oxygen fluorides are strong oxidizing agents.

Oxygen difluoride, OF2, is a colorless gas, with a characteristic pungent odor. Highly toxic, it has a density of 1.521 g/cm3 at – 145°C, a melting point of –224°C, and a boiling point of – 145°C. It gradually decomposes into the individual elements at a temperature of about 200°C. Pure oxygen difluoride is not explosive. It dissolves poorly in water, undergoing hydrolysis. Liquid OF2 is freely soluble in liquid fluorine, oxygen, and ozone. In terms of chemical properties, OF2 is a strong oxidizing agent; it fluorinates metals on slight heating and explodes on reaction with water, hydrogen, or halogens when triggered by a spark or when heated. OF2 is obtained by the fluorination of an aqueous solution of caustic soda or caustic potash: 2F2 + 2NaOH = OF 2+ 2NaF + H2O; it is also obtained by the electrolysis of an aqueous HF solution.

Dioxygen difluoride, O2F2, is an unstable compound. On interaction with Lewis acids, it forms salts of the dioxygen cation O+2; for example, O2F2 + SbF5 = O2SbF6 + l/2F2. It is prepared from a mixture of fluorine and oxygen in a glow discharge at a temperature of – 196°C. It is used in the laboratory as a strong fluorinating or oxidizing agent.

REFERENCES

See references under .

A. V. PANKRATOV