The%20Halogens

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• The Halogens
• Group 17 on the Periodic Table
• By Christine Ngo, Kristal Espana, Rebecca
  Odusola, Jeremy Bekkouche

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The Halogens

• Group of nonmetals
• All elements in this group are reactive
• Fluorine, Chlorine, Bromine, Iodine and Astatine
  are all in the halogens group.

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Fluorine

• Gas at room temperature and extremely reactive
• Isolated by Henri Moissan in 1886
• Can be found in toothpaste and in water systems
  where they help to prevent tooth decay

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Chlorine

• Greenish-yellow gas with a noticeable odor
• In high concentration it will be toxic
• Was used in World War I as a poison gas
• Prepared by Scheele in later 1700, proved tobe an
  element by Davy in 1810
• Used in swimming pools to get rid of any bacteria

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Bromine

• Reddish-brown fuming liquid with a chlorine-like
  smell.
• Isolated in pure form by Balard in 1826.
• Only non-metal that is liquid at normal room
  conditions.
• Can cause painful burns that heal slowly when
  applied on the skin.
• Used for dyes,disinfectants,and photographic
  chemicals.

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Iodine

• It was discovered in 1811 by Curtis
• Dark gray solid with a faint metallic luster
• When heated, it turns to a violet gas
• Important element in the human diet
• Crucial for a properly working thyroid gland
• Used in table salt
• Used medically for the thyroid and anything that
  has to deal with that gland.

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Astatine

• Last of the known halogens in 1940 by Corson and
  others at the university in California.
• It is radioactive and its name, from the Greek
  astatos, means uristable
• Astatine is expected to react like others
  halogens but less active
• Should be a tiny quantities of astatine in the
  earth's crust.

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