Tin(IV) fluoride is a
chemical compound
A chemical compound is a chemical substance composed of many identical molecules (or molecular entities) containing atoms from more than one chemical element held together by chemical bonds. A molecule consisting of atoms of only one element ...
of
tin
Tin is a chemical element; it has symbol Sn () and atomic number 50. A silvery-colored metal, tin is soft enough to be cut with little force, and a bar of tin can be bent by hand with little effort. When bent, a bar of tin makes a sound, the ...
and
fluorine
Fluorine is a chemical element; it has Chemical symbol, symbol F and atomic number 9. It is the lightest halogen and exists at Standard temperature and pressure, standard conditions as pale yellow Diatomic molecule, diatomic gas. Fluorine is extre ...
with the
chemical formula
A chemical formula is a way of presenting information about the chemical proportions of atoms that constitute a particular chemical compound or molecule, using chemical element symbols, numbers, and sometimes also other symbols, such as pare ...
SnF
4. It is a white solid. As reflected by its melting point above 700 °C, the tetrafluoride differs significantly from the other tetrahalides of tin.
Synthesis and reaction
SnF
4 can be prepared by the reaction of
tin(IV) chloride
Tin(IV) chloride, also known as tin tetrachloride or stannic chloride, is an inorganic compound of tin and chlorine with the formula SnCl4. It is a colorless hygroscopic liquid, which fumes on contact with air. It is used as a precursor to other ...
with anhydrous
hydrogen fluoride
Hydrogen fluoride (fluorane) is an Inorganic chemistry, inorganic compound with chemical formula . It is a very poisonous, colorless gas or liquid that dissolves in water to yield hydrofluoric acid. It is the principal industrial source of fluori ...
:
:SnCl
4 + 4HF → SnF
4 + 4HCl
When treated with alkali metal fluorides (e.g. KF), tin(IV) fluoride forms hexafluorostannates:
:
In K
2SnF
6, tin adopts an octahedral geometry.
Otherwise, SnF
4 behaves as a
Lewis acid
A Lewis acid (named for the American physical chemist Gilbert N. Lewis) is a chemical species that contains an empty orbital which is capable of accepting an electron pair from a Lewis base to form a Lewis adduct. A Lewis base, then, is any ...
forming a variety of adducts with the formula L
2·SnF
4 and L·SnF
4.
Structure
Unlike the heavier tin tetrahalides, which contain tetrahedrally coordinated tin, tin(IV) fluoride contains octahedrally coordinated tin. The octahedra share four corners. There are two terminal, unshared, fluorine atoms ''
trans
Trans- is a Latin prefix meaning "across", "beyond", or "on the other side of".
Used alone, trans may refer to:
Sociology
* Trans, a sociological term which may refer to:
** Transgender, people who identify themselves with a gender that di ...
'' to one another.
[Inorganic Chemistry aperback2d Edition, Housecroft, Sharpe, 2004, Pearson Education , ] The melting point of SnF
4 is much higher (700 °C) than the other tin(IV) halides: (
SnCl4, −33.3 °C;
SnBr4, 31 °C;
SnI4, 144 °C).
The structure can also be contrasted with the tetrafluorides of the lighter members of group 14, (
CF4,
SiF4 and
GeF4), all of which in the solid state form molecular crystals.
See also
*
Stannous fluoride
Tin(II) fluoride, commonly referred to commercially as stannous fluoride (from Latin ', 'tin'), is a chemical compound with the formula SnF2. It is a colourless solid used as an ingredient in toothpastes.
Oral health benefits
Stannous fluoride is ...
References
{{fluorides
Fluorides
Tin(IV) compounds
Metal halides