Periodic Trends 1

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Periodic Trends 1

• A periodic trend
• Changes in physical or chemical properties,
  formulas or microscopic attributes that have some
  pattern in the Periodic Table
• Patterns have breaks and there are exceptions
• Going across a row or down a column
• Big picture trends from one end to another
  end
• Trends in macroscopic properties
• physical properties changes in MP and BP, color,
  hardness, conductivity
• chemical properties changes in the way in which
  elements react with other elements or compounds

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Periodic Trends 2

• Trends in microscopic properties
• Measured values ionization energy, electron
  affinity, atomic size, ionic size
• Derived values effective nuclear charge,
  electronegativity
• Trends in formulas
• Formulas are a consequence of how matter is
  organized on the microscopic level
• Changes in formulas suggest going from one type
  of organization to another

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Melting Points of Oxides
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Melting Point of the Hydrides
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Melting Points of Sulfides
6
Melting Points of Chlorides
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Some properties of element in the first full row
of the PT
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Some properties of element in the second full row
of the PT
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Some properties in the first column of the
Periodic Table (alkali metals)
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Some properties in the second column of the
Periodic Table (alkaline earth metals)
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Some properties in the 17th column of the
Periodic Table (halogens)
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Chemical and Physical Properties of some compound
in Periodic Table
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Microscopic Periodic Trends

• Ionization energy
• How much energy does it take to remove an
  electron from the nucleus it is associated with
• The easiest electron to remove is furthest from
  nucleus
• Atomic size ionic size
• How big are atoms and ions
• What is the distance from the center of the
  nucleus to the outermost electron
• Effective nuclear charge
• What nuclear charge is felt as we go further
  away from nucleus
• Electronegativity
• What is the relative tendency of elements to hold
  their own electrons and to compete for the
  electrons of other elements
• Need to know where electrons are located