Atoms and the Periodic Table

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UNIT VIII

• Atoms and the Periodic Table
• Lesson1
• Atomic Number, Atomic mass, Isotopes review

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VIII.1 THE STRUCTURE OF THE ATOM

• Some vocabulary
• PROTONS 
• NEUTRONS
• Elements are differentiated from one another
  by the number of protons in the nucleus

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VIII.1 THE STRUCTURE OF THE ATOM

• ELECTRONS
•  
• ATOMIC NUMBER

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What the periodic table tells you

• Atomic mass

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• What if the atom is NOT neutral???
• It means it is an _______

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VIII.1 THE STRUCTURE OF THE ATOM

• ION when electrons are added or taken away from
  an atom, an ion is formed (with a charge)
• Ex If an extra electron is added to a neutral
  Cl atom
• protons
• electrons
• Charge on nucleus
• Charge of Electrons
• Total Charge of Atom

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VIII.1 THE STRUCTURE OF THE ATOM
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VIII.1 THE STRUCTURE OF THE ATOM
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VIII.1 THE STRUCTURE OF THE ATOM

• Ex If 2 electrons (e-) are removed from Barium
  (Ba)
• protons
• electrons
• Charge on nucleus
• Charge of Electrons
• Total Charge of Atom

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VIII.1 THE STRUCTURE OF THE ATOM

• Ex How many electrons are possessed by Ca2?
• How many protons are in Ca2 ?

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VIII.1 THE STRUCTURE OF THE ATOM

• Atomic mass
• Atomic number
•  
• Neutrons (ATOMIC MASS) - (ATOMIC NUMBER)

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VIII.1 THE STRUCTURE OF THE ATOM

• Ex Find the number of protons, neutrons and
  electrons possessed by the following atoms
• a. C
• b. Zn3
•  

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VIII.1 THE STRUCTURE OF THE ATOM

• Isotopes Atoms with same of protons, but
  different of neutrons therefore different
  atomic mass!
• If you add a proton to an atom, a new element is
  produced
• C p ? N
• If you add a neutron to an atom, you get the same
  element but heavier in other words an isotope!
• C n ? C

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VIII.1 THE STRUCTURE OF THE ATOM

• Three H-isotopes
• H H Hydrogen
• H D Deuterium
• H T Tritium
• C-isotopes

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VIII.1 THE STRUCTURE OF THE ATOM

• E. Natural Mixtures of Isotopes
• Molar Mass --- is really an average value for a
  MIXTURE of isotopes

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VIII.1 THE STRUCTURE OF THE ATOM

• Ex The following mixtures of isotopes are found
  in nature calculate the expected molar mass of
  a the mixture.
•  
• a) Ga-69 60.0 , Ga-71 40.0

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VIII.1 THE STRUCTURE OF THE ATOM

• b) Ag-107 51.8, Ag-109 48.2

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Homework

• Hebden p. 146 13-17
• p. 147 19 (fill in table)
• p. 149 22 (fill in table)
• p. 150 23 a, d and 24