The Periodic Table

1
The Periodic Table
2
The Periodic Table

• History and Development
• Arrangement and Organization of Elements
• Finding Information

3
History of the Table

• What was the table like before Demetri
  Mendeleev ?
• What did he do to improve it?
• Has it changed since Mendeleev?

4
Early Study of the Elements

• Beguyer de Chancourtois - 1862 - geologist
  arranged elements by atomic weights about a
  cylinder
• Meyer 1895 plotted atomic volume against
  molecular weight found 2 short periods and 2
  long periods on his graph
• Newlands - English
• 1864 - Law of Octaves - every 8th element has
  similar properties

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Stanislao Cannizzaro

• Discovered a new way to calculate atomic mass
• Scientists everywhere agreed this was a very
  reliable method
• Provided a sense of order for the elements

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The Periodic Law

• The physical and chemical properties of the
  elements are periodic functions o their atomic
  numbers.
• OR when elements are arranged in order of
  increasing atomic number, elements with similar
  properties appear at regular intervals

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Development of Periodic Table

• Periodic Law 1869
• allowed Mendeleev to predict properties of
  unknown elements

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Mendeleevs Periodic Table

• arranged elements according to
• increasing atomic weights
• physical properties
• metal/nonmetal
• melting points, boiling points, density,
  reactivity
• Many later discoveries support Mendeleevs table

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Missing elements 44, 68, 72, 100 amu
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Mendeleevs Table - Irregularities

• When arranged by similar properties, a few
  elements were out of place by atomic mass
• There were some empty spaces in the table

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Moseleys Contribution

• Moseley, Henry Gwyn Jeffreys
• 18871915, English physicist.
• Studied the relations among bright-line spectra
  of different elements.
• Derived the ATOMIC NUMBERS from the frequencies
  of vibration of X-rays emitted by each element.
• Moseley concluded that the atomic number is equal
  to the charge on the nucleus.
• This work explained discrepancies in Mendeleevs
  Periodic Table.

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The Periodic Table
The elements on the table are now arranged
according to increasing Atomic Number
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Organization of Periodic Table

• period
• group
• type of element
• physical properties
• mp, bp, density, conductivity
• chemical reactivity
• ionization energy, electron affinity,
  electronegativity

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Organization and Arrangement

• period - horizontal row
• group or family - vertical column

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Types of Elements

• metals
• nonmetals
• metalloids - semimetals

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Periodic Table of the Elements
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Family Names

• Group IA alkali metals
• Group IIA alkaline earth metals
• Group VIIA halogens
• Group VIIIA noble gases
• metalloids
• transition metals
• inner transition metals
• lanthanum series rare earths
• actinium series trans-uranium series

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The Periodic Table
Know what information you can find and where to
find it
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Finding Information

• A periodic table is always available to you. To
  be successful in chemistry, you must know
• the names and symbols
• later many of the ions that form
• how to find number of protons, neutrons, and
  electrons in an element
• how to read the other information on the table.

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Information foundon the Periodic Table

• Chemical symbol
• Atomic number
• Atomic Mass
• Protons in atom
• Electrons in atom
• Neutrons in atom
• Metal / Nonmetal

• Chemical activity
• Oxidation number
• Energy levels
• Electron configuration
• Chemical Families
• Natural / Manmade
• Physical state at room temperature

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Metals
Nonmetals
Noble gases do not react
Chemical Activity
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1
0
2
-1
-2
-3
4
3
M o s t a r e 1 o r 2
Oxidation Number
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s
p
1
He
2
3 d
3
4
5
6
7
4 f
Energy levels and sublevels
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The End