Arsenic pentafluoride is a chemical compound

Chemical compound

A chemical compound is a pure chemical substance consisting of two or more different chemical elements that can be separated into simpler substances by chemical reactions. Chemical compounds have a unique and defined chemical structure; they consist of a fixed ratio of atoms that are held together...

 of arsenic

Arsenic

Arsenic is a chemical element with the symbol As, atomic number 33 and relative atomic mass 74.92. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. It was first documented by Albertus Magnus in 1250.Arsenic is a metalloid...

 and fluorine

Fluorine

Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

. The oxidation state

Oxidation state

In chemistry, the oxidation state is an indicator of the degree of oxidation of an atom in a chemical compound. The formal oxidation state is the hypothetical charge that an atom would have if all bonds to atoms of different elements were 100% ionic. Oxidation states are typically represented by...

 of arsenic is +5.

Synthesis

Arsenic pentafluoride can be prepared by direct combination of arsenic and fluorine:

2As + 5F₂ → 2AsF₅

It can also be prepared by the reaction of arsenic trifluoride

Arsenic trifluoride

Arsenic trifluoride is a chemical compound of arsenic and fluorine with the formula AsF3. It is a colorless liquid which reacts readily with water.-Preparation and properties:It can be prepared by reacting hydrogen fluoride, HF, with arsenic trioxide:...

 and fluorine

Fluorine

Fluorine is the chemical element with atomic number 9, represented by the symbol F. It is the lightest element of the halogen column of the periodic table and has a single stable isotope, fluorine-19. At standard pressure and temperature, fluorine is a pale yellow gas composed of diatomic...

:

AsF₃ + F₂ → AsF₅

Properties

Arsenic pentafluoride is a colourless gas and has a trigonal bipyramidal structure. In the solid state the axial As-F bond lengths are 171.9 pm and the equatorial 166.8 pm.

Reactions

Arsenic pentafluoride forms halide complexes and is a powerful acceptor as shown by the reaction with sulfur tetrafluoride

Sulfur tetrafluoride

Sulfur tetrafluoride is the chemical compound with the formula SF4. This species exists as a gas at standard conditions. It is a corrosive species that releases dangerous HF upon exposure to water or moisture...

forming an ionic complex.

AsF₅ + SF₄ → SF₃⁺ + AsF₆⁻