Beryllium iodide is the 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...

 with the formula

Chemical formula

A chemical formula or molecular formula is a way of expressing information about the atoms that constitute a particular chemical compound....

 BeI₂. It is very hygroscopic and reacts violently with water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

, forming hydroiodic acid.

Reactions

Beryllium iodide can be prepared by reacting beryllium

Beryllium

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

 metal with elemental iodine

Iodine

Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....

 at temperatures of 500°C to 700°C:

Be

Beryllium

Beryllium is the chemical element with the symbol Be and atomic number 4. It is a divalent element which occurs naturally only in combination with other elements in minerals. Notable gemstones which contain beryllium include beryl and chrysoberyl...

  + I₂

Iodine

Iodine is a chemical element with the symbol I and atomic number 53. The name is pronounced , , or . The name is from the , meaning violet or purple, due to the color of elemental iodine vapor....

  → BeI₂

Beryllium iodide is also formed when beryllium carbide

Beryllium carbide

Beryllium carbide, or Be2C, is a metal carbide. Similar to diamond, it is a very hard compound.-Preparation:Beryllium carbide is prepared by heating the elements beryllium and carbon at elevated temperatures...

 reacts with hydrogen iodide

Hydrogen iodide

Hydrogen iodide is a diatomic molecule. Aqueous solutions of HI are known as iohydroic acid or hydroiodic acid, a strong acid. Gas and aqueous solution are interconvertible...

 in the gas

Gas

Gas is one of the three classical states of matter . Near absolute zero, a substance exists as a solid. As heat is added to this substance it melts into a liquid at its melting point , boils into a gas at its boiling point, and if heated high enough would enter a plasma state in which the electrons...

 phase:

Be₂C

Beryllium carbide

Beryllium carbide, or Be2C, is a metal carbide. Similar to diamond, it is a very hard compound.-Preparation:Beryllium carbide is prepared by heating the elements beryllium and carbon at elevated temperatures...

  + 4 HI

Hydrogen iodide

Hydrogen iodide is a diatomic molecule. Aqueous solutions of HI are known as iohydroic acid or hydroiodic acid, a strong acid. Gas and aqueous solution are interconvertible...

  → 2 BeI₂ + CH₄

Methane

Methane is a chemical compound with the chemical formula . It is the simplest alkane, the principal component of natural gas, and probably the most abundant organic compound on earth. The relative abundance of methane makes it an attractive fuel...

The iodine in beryllium iodide is easily replaced with the other halogens; it reacts with 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...

 giving beryllium fluoride

Beryllium fluoride

Beryllium fluoride is the inorganic compound with the formula BeF2. This white solid is the principal precursor for the manufacture of beryllium metal.-Structure and bonding:...

 and fluorides of iodine

Interhalogen

The halogens react with each other to form interhalogen compounds.The general formula of most interhalogen compounds is XYn, where n = 1, 3, 5 or 7, and X is the less electronegative of the two halogens...

, with chlorine

Chlorine

Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...

 giving beryllium chloride

Beryllium chloride

Beryllium chloride is an inorganic compound with the formula BeCl2. It is a colourless, hygroscopic solid that dissolves well in many polar solvents...

, and with bromine

Bromine

Bromine ") is a chemical element with the symbol Br, an atomic number of 35, and an atomic mass of 79.904. It is in the halogen element group. The element was isolated independently by two chemists, Carl Jacob Löwig and Antoine Jerome Balard, in 1825–1826...

 giving beryllium bromide

Beryllium bromide

Beryllium bromide is the chemical compound with the formula BeBr2. It is very hygroscopic and dissolves well in water.-Reactions:Beryllium bromide can be prepared by reacting beryllium metal with elemental bromine at temperatures of 500°C to 700°C:...

. Beryllium iodide also reacts violently with oxidising agents such as chlorate and permanganate to give purple vapour of iodine. The solid and vapor are both flammable in air.