Make your own free website on Tripod.com
Elements Around the World

Group 17 Elements: Halogens

Home
Transistion Metals
Group VI A Elements
Group 17 Elements: Halogens
Group 2a Elements- Alkaline Earth Metals
Group 1a-Alakali Metals

Location:
The Halogens are located one column from the far right hand side of the periodic table.

Physical Properties:
-The halogens are diatomic molecules in their natural form.

-The halogens show a number of trends when moving down the group, for instance, decreasing electronegativity and reactivity, increasing melting and boiling point.                                                                                                           

Fluorine is pale yellow gas. It is the least dense and most chemically active.  It displaces the other halogens from their compounds and even displaces oxygen from water.                            –Chlorine is a yellow-green gas. It is more dense and less reactive than fluorine.                                                                                                -Bromine is a dark red liquid.                                                          

-Iodine is a grayish black solid and is the least chemically active of the four; however, among the nonmetals only oxygen is more reactive than iodine.


Uses:

-Chlorine and iodine are both used as disinfectants for such things as drinking water, swimming pools, fresh wounds, dishes, and surfaces.
-Chlorine is used in many fabric bleaches and is used to produce most paper products.           –Hydrochloric acid is very important for industrial cleaning of galvanized steel; it is also used in the creation of other chemical compounds.

Interesting Facts:

-The term halogen was coined to mean elements which produce a salt in union with a metal. It comes from 18th century scientific French nomenclature based on erring adaptations of Greek roots.

           

Reaction Patterns:

-Not found as free elements in nature.

-Very high reactivity because of their electron configuration, ns2np5

-They are typically found as halide ions(X-) in minerals and sea water.

-Astatine does not factor into the reaction patters because all known isotopes are radioactive.  It   has a short half-life of 8.3 hours.

-Halogens have high electronegativity values and tend to form polar covalent bonds with other nonmetals and ionic bonds with metals while in their lower oxidation states.

-Metals with higher oxidation states form form polar covalent bonds such as TiCl4.

-Halogen Halides are prepared by reacting a halogen(X2) with H2.  This forms 2HX.

-Halogen halides can also be prepared by treating halide salts with an acid.

-Halogens can react with each other to produce interhalogen compounds.