Iodine monofluoride
Encyclopedia
Iodine monofluoride is an interhalogen compound of iodine
and fluorine
with formula IF. It is a chocolate-brown solid that decomposes at 0 C, disproportionating
to elemental iodine and iodine pentafluoride
:
However, its molecular properties can still be precisely determined by spectroscopy
: the iodine-fluorine distance is 190.9 pm and the I−F bond dissociation energy
is around 277 kJ mol−1. At 298 K
, its standard enthalpy change of formation
is ΔHf° = −95.4 kJ mol−1, and its Gibbs free energy
is ΔGf° = −117.6 kJ mol−1.
It can be generated, albeit only fleetingly, by the reaction of the elements at −45 °C in CCl3F
:
It can also be generated by the reaction of iodine with iodine trifluoride
at −78 °C in CCl3F:
The reaction of iodine with silver(I) fluoride
at 0 °C also yields iodine monofluoride:
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....
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...
with formula IF. It is a chocolate-brown solid that decomposes at 0 C, disproportionating
Disproportionation
Disproportionation, also known as dismutation is used to describe a specific type of redox reaction in which a species is simultaneously reduced and oxidized so as to form two different products....
to elemental iodine and iodine pentafluoride
Iodine pentafluoride
Iodine pentafluoride is an interhalogen compound with chemical formula IF5. It is a fluoride of iodine. It is a colourless or yellow liquid with a density of 3.250 g cm−3. It was first synthesized by Henri Moissan in 1891 by burning solid iodine in fluorine gas...
:
- 5 IF → 2 I2 + IF5
However, its molecular properties can still be precisely determined by spectroscopy
Spectroscopy
Spectroscopy is the study of the interaction between matter and radiated energy. Historically, spectroscopy originated through the study of visible light dispersed according to its wavelength, e.g., by a prism. Later the concept was expanded greatly to comprise any interaction with radiative...
: the iodine-fluorine distance is 190.9 pm and the I−F bond dissociation energy
Bond dissociation energy
In chemistry, bond-dissociation energy or D0, is one measure of the bond strength in a chemical bond. It is defined as the standard enthalpy change when a bond is cleaved by homolysis, with reactants and products of the homolysis reaction at 0 K...
is around 277 kJ mol−1. At 298 K
Kelvin
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all...
, its standard enthalpy change of formation
Standard enthalpy change of formation
The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy that accompanies the formation of 1 mole of a substance in its standard state from its constituent elements in their standard states...
is ΔHf° = −95.4 kJ mol−1, and its Gibbs free energy
Gibbs free energy
In thermodynamics, the Gibbs free energy is a thermodynamic potential that measures the "useful" or process-initiating work obtainable from a thermodynamic system at a constant temperature and pressure...
is ΔGf° = −117.6 kJ mol−1.
It can be generated, albeit only fleetingly, by the reaction of the elements at −45 °C in CCl3F
Trichlorofluoromethane
Trichlorofluoromethane, also called freon-11, CFC-11, or R-11, is a chlorofluorocarbon. It is a colorless, nearly odorless liquid that boils at about room temperature.- Uses :It was the first widely used refrigerant...
:
- I2 + F2 → 2 IF
It can also be generated by the reaction of iodine with iodine trifluoride
Iodine trifluoride
Iodine trifluoride is an interhalogen compound with the chemical formule IF3. It is a yellow solid which decomposes above −28 °C. It can be synthesised from the elements, but care must be taken to avoid the formation of IF5.-Reactions:...
at −78 °C in CCl3F:
- I2 + IF3 → 3 IF
The reaction of iodine with silver(I) fluoride
Silver(I) fluoride
Silver fluoride , also known as argentous fluoride and silver monofluoride, is a compound of silver and fluorine. It is a ginger-coloured solid, melting point 435 °C, which blackens on exposure to moist air. Unlike other silver halides such as silver chloride it is soluble in water to the extent...
at 0 °C also yields iodine monofluoride:
- I2 + AgF → IF + AgI