P8-+Halogen

=Halogens=

Group Number and Elements:
Halogens are listed in the Periodic Table of Elements in group 17. In group 17, there are five elements. They are Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At).

States of Matter:
Halogens come in three states of matter- solid, liquid, and gas. Iodine and Astatine are solids, Bromine is a liquid, and Fluorine and Chlorine are gases.

Physical Properties:
The elements that make up the Halogen group have their own boiling and melting points(with one exception).

Fluorine: melting point- -218ºc, boiling point- -188ºc Chlorine: melting point- -101ºc, boiling point- -34ºc Bromine: melting point- -1ºc, boiling point- -59ºc Iodine: melting point- -114ºc, boiling point- -184ºc Astatine: does not have a melting or boiling point because it's found in trace amounts and it only survives for about seven hours.

Also, each element has their own color(with one exception). Fluorine is a pale yellow, Chlorine is a yellow-green, Bromine is a mix between red and brown, Iodine is purple, and Astatine comes in such small amounts that the color is not visible. Plus, Halogens can be soluble.

Chemical Properties:
Halogens have Chemical properties. Some elements in the Halogen group have the ability to oxidise, and some are combustible. Fluorine has the strongest ability to oxidise and Chlorine has the second strongest ability to oxidise. Chlorine is combustible when it mixes with Potassium to form Potassium Chloride. It's used as an oxidant in fireworks and matches. Also, Halogens can react easily with a lot of things. Halogens react well in compounds.

Interesting Facts:
One interesting fact is Halogens mean "salt-former". Another is that Halogens exist at room-temperature. Halogens also bond well with metals and elements from group 1. Halogens are very reactive and as you move up the table in group 17, the reactive ability increases. Another interesting fact is that Chlorine gas (Cl2), also known as mustard gas, was used during World War I was the start of chemical warfare.

Common Uses:
Halogens are used in many useful ways. Iodine is used in halogen lamps, Fluorine is used to make plastics(as a compound) in the prevention of to oth decay, and Chlorine is used to purify water, making pipes, and bleaching.

 Sources:

 * Www.rsc.org //. Web. 22 Oct. 2009. . //
 * Www.chemicalelements.com //. Yinon Bentor, 2009. Web. 22 Oct. 2009. . //
 * Www.chem4kids.com //. Andrew Rader Studios, 2009. Web. 22 Oct. 2009. . //
 * Modern_periodic_table //. Photograph. //Www.bbc.co //. Web. 22 Oct. 2009. Www.chemcool.com //. Web. 26 Oct. 2009. <http://www.chemcool.com/regents/periodictable/aim2.htm>. //
 * ////Ahoy.tk-jk.net//. Mackenzie J. Gregory, 2009. Web. 26 Oct. 2009. <http://ahoy.tk-jk.net/macslog/SlaughteratBariSouthernIt.html>.//
 * <span style="color: #000000; font-family: Arial,Helvetica,sans-serif;"> // Photograph. ///www.gmagazine.com// . 2008. Web. 26 Oct. 2009. <http://www.gmagazine.com.au/998/ask-g-high-intensity-halogen-lights>. //

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