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Ions

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					                                                     Isn’t it
                                                      Ionic!

                         Ions
                   Charged particles
                (atoms that have lost or
                    gained electrons)                           Alanis Morissete’s 1st
                                                                attempt at a hit song.


         Reminder:
         _________ lose electrons & have a _________ charge.
         (Example: _____________)
         _________ gain electrons & have a _________ charge.
         (Example: _____________)

Ions are shown with an element symbol & it’s charge (as a superscript).

                 +
            K
                                              Oxidation Number
                                                - the charge on an ion
                                  (indicates how many e- have been gained or lost)

         Potassium has
         ____________ one
         electron. (CATION)


    ION         Gained or Lost    How         Cation or            Metal or
                  electrons?     many?         Anion?             Nonmetal?
  Li+
  Se2-
  Br-
  Mg2+
  Al3+
Forming Ionic Bonds from Ions




  Electrons are transferred forming IONS.




                                           IONIC BOND
                                       Attraction between a
                                      cation (+ charge) and an
                                           ion (- charge)
                                       (Once they are combined, the
               NaCl                        compound is neutral!)




              Ionic Compounds have a very ordered structure
                   due to the alternating + and – charges.


              Ionic Compounds are often referred to as
                       CRYSTALS or SALTS.
   Ionic Bonds are very strong due to the attractive forces
   between the ions.
   If placed in water, however, the lattice structure comes
   apart…freeing the ions    DISSOCIATION


                                             When salts
                                      (IONIC COMPOUNDS)
                                       are dissolved in water,
                                        the ions can conduct
                                             electricity!




Why must a salt be dissolved in water to conduct electricity?
  As a solid, the ionic compound has no charge & remains in
  crystal form. (No charges = no electricity)
  When placed in water, the ions (charged particles) are free to
  move!



   Summary: Characteristics of Ionic Compounds

      Ionic bonds are caused by the transfer of e-
        occur between a metal (cation) and a nonmetal (anion)
        called SALTS or CRYSTALS
        have high melting & boiling points
        electrically neutral as a compound, but will dissociate
         (come apart)in water, freeing ions to conduct electricity

				
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