Classifications of the Elements by ewghwehws

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									Classifications of the Elements
   Classifications of the Elements
• Metals are found on the left and center of the
  periodic table.
   Classifications of the Elements
• Metals are usually gray, shiny, solid at 20oC,
  malleable, ductile, good conductors, and have
  moderate to high melting and boiling points.




• Metals tend to lose electrons (be oxidized)
  during chemical reactions.
   Classifications of the Elements
• All of the properties that are typical of a metal
  are referred to as metallic character.
   Classifications of the Elements
• Metallic character increases from right to left
  across each period on the periodic table.
   Classifications of the Elements
• Metallic character increases from top to bottom
  in each group on the periodic table.
   Classifications of the Elements
• Francium is considered the most metallic of all
  the metals! It has the most metallic character.




• The closer francium → the more metallic
   Classifications of the Elements
• Nonmetals are found on the upper right of the
  periodic table.
   Classifications of the Elements
• Nonmetals come in many colors and phases.
• Nonmetals have lower melting and boiling points
  than metals. Solid nonmetals tend to be brittle
  and are poor conductors of heat and electricity.




• Nonmetals tend to gain electrons (be reduced)
  during chemical reactions.
   Classifications of the Elements

• All of the properties that are typical of a nonmetal
  are referred to as nonmetallic character.




• Hydrogen is neither a metal nor a nonmetal.
   Classifications of the Elements
• Nonmetallic character increases from left to
  right across each period on the periodic table.
   Classifications of the Elements
• Nonmetallic character increases from bottom
  to top in each group on the periodic table.
   Classifications of the Elements
• Fluorine is considered the most nonmetallic of
  all the nonmetals!




• The closer fluorine → the more nonmetallic
   Classifications of the Elements

Ex. (1) The most metallic of all the elements are
        found in the (lower/upper) __________
                                       lower
        (left/right) __________ of the periodic table.
                         left

Ex. (2) The most nonmetallic of all the elements are
        found in the (lower/upper) __________
                                       upper
        (left/right) __________ of the periodic table.
                        right
   Classifications of the Elements
• The metalloids are found along the zig-zag line
  of the periodic table.
   Classifications of the Elements
• The metalloids are elements have some metallic
  properties and same nonmetallic properties.




• The metalloids are B, Si, Ge, As, Sb, and Te.
   Classifications of the Elements
• One important property of metalloids is that they
  are semiconductors.




• This property makes metalloids important in the
  computer chip industry!
   Classifications of the Elements
• The noble gases are found in the last column of
  the periodic table.
   Classifications of the Elements
• The noble gases are elements that are all gases
  at ordinary temperatures.




• The noble gases are extremely unreactive and
  so rarely form compounds with other elements.
• The noble gases are He, Ne, Ar, Kr, Xe, and Rn.
   Classifications of the Elements
• The alkali metals are found in the first column
  of the periodic table.
   Classifications of the Elements
• The alkali metals are soft, gray, shiny, and have
  low melting and boiling points for metals.




• The alkali metals are extremely reactive and so
  are never found pure in nature.
• The alkali metals are Li, Na, K, Rb, Cs, and Fr.
   Classifications of the Elements
• The alkaline earth metals are found in the
  second column of the periodic table.
   Classifications of the Elements
• The alkaline earth metals are gray, shiny, and
  are harder than alkali metals.




• The alkaline earth metals are very reactive and
  so are never found pure in nature.
• The alkaline earth metals are Be, Mg, Ca, Sr
  Ba, and Ra.
   Classifications of the Elements
• The halogens are found in the second to last
  column of the periodic table.
   Classifications of the Elements
• The halogens are colorful elements that easily
  react with metals to form salt compounds.




• The halogens are highly reactive and so are
  never found pure in nature.
• The halogens are F, Cl, Br, I and At.
   Classifications of the Elements
• The transition elements are found in the middle
  (groups 3 - 12) of the periodic table.
   Classifications of the Elements
• The transition elements have high melting and
  boiling points and have higher densities than
  alkali or alkaline earth metals.




• Many transition elements can often form more
  than one compound with the same element.
  (i.e. FeO and Fe2O3, NiCl2 and NiCl3, Cu2S and CuS)
   Classifications of the Elements
• Many transition elements can also form
  compounds whose solid hydrates are colored
  and whose aqueous solutions are colored.




• Most compounds in nature are white and their
  aqueous solutions are colorless!
   Classifications of the Elements
• The rare earth elements are found at the very
  bottom of the periodic table.
   Classifications of the Elements
• Facts about rare earth elements here!
   Classifications of the Elements
• Elements come in all phases at room temperature.
• Helium (He), neon (Ne), argon (Ar), krypton (Kr),
  xenon (Xe), radon (Rn), hydrogen (H), nitrogen
  (N), oxygen (O), fluorine (F), and chlorine (Cl),
  are all gases at room temperature (20oC).
   Classifications of the Elements
• Mercury (Hg) and bromine (Br) are the only
  liquid elements at room temperature (20oC).




• All of the remaining elements are solids at room
  temperature.
   Classifications of the Elements
• When an element is in its pure form, it is called a
  free element.

• When in their pure form, noble gases exist as a
  collection of single atoms.

• This is why noble gases are called monoatomic
  free elements.



   helium   neon    argon    krypton   xenon   radon
   Classifications of the Elements
• When in their pure form, there are seven elements
  that exist as a collection of pairs of atoms.



  Fluorine             oxygen            hydrogen              nitrogen




             bromine            iodine              chlorine
• These elements are called the diatomic free
  elements.
 Classifications of the Elements




 A balloon filled   A balloon filled
with hydrogen gas   with helium gas
  Classifications of the Elements
• The mnemonic device…
             “F O H N Br I Cl”
 helps to remember the diatomic free elements.

            F2 O2 H2 N2 Br2 I2 Cl2
Classifications of the Elements
             Element   Chemical
 Element
             Symbol    Formula
  Fluorine      F         F2
  Oxygen        O         O2
 Hydrogen       H         H2
 Nitrogen       N         N2
 Bromine        Br       Br2
   Iodine        I        I2
 Chlorine       Cl       Cl2

								
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