The Periodic Table

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• The Periodic Table

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The Language of Chemistry

• CHEMICAL ELEMENTS
• pure substances that cannot be changed into
  other substances.

Aluminum
Bromine
Sodium
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The Language of Chemistry

• The elements, their names, and symbols are given
  on the PERIODIC TABLE
• How many elements are there?

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The Periodic Table

• Dmitri Mendeleev (1834 - 1907)

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Dmitri Mendeleev (1869)

• In 1869 Mendeleev and Lothar Meyer (Germany)
  published nearly identical classification
  schemes for elements known to date.
• Mendeleev gets most credit as he could make
  accurate predictions about elements which he
  thought must exist, but were unknown.
• The Periodic Table is based on the similarity of
  properties and reactivities exhibited by certain
  elements.
• Later, Henri Moseley (England, 1887-1915)
  established that each elements has a unique
  atomic number, which is how the current periodic
  table is organized.

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Glenn Seaborg(1912-1999 )

• Discovered 8 new elements.
• Only living person for whom an element was named.

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Periods in the Periodic Table
The rows are the Periods of the Periodic
Table. As you go down the Periodic Table the
elements become more reactive.
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Groups in the Periodic Table
The elements in the columns are the Groups of the
Periodic Table.
Elements in groups react in similar ways!
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Group 1 Alkali Metals
Reaction of potassium H2O
Cutting sodium metal
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Group 2 Alkaline Earth Metals
Magnesium
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Group 7 The Halogens Fluorine, Chlorine,
Bromine, Iodine
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Group 8 The Noble GasesHelium, Neon, Argon,
Krypton, Xenon, Radon

• Lighter than air balloons
• Neon signs
• Very Unreactive

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Transition Elements

• Lanthanides and actinides

Iron in air gives iron(III) oxide
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Names of Elements

• Each element is given a separate name
• Hydrogen, carbon, oxygen, iron and aluminium are
  some well known elements
• Several elements, such as curium and einsteinium
  are named after well known scientists
• Others such as francium, germanium and americium
  are named after their country of discovery

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Where do all the Chemical Elements come from?

• Only the first 92 elements occur naturally and
  can be found in the Earth, air or water.
• Nuclear scientists have produced these chemical
  elements inside nuclear reactors
• Many of these new elements do not last very long
  and often break down by giving off nuclear
  radiation.

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Atomic Symbols

• Each element is also given a one letter or two
  letter symbol which is used as a shorthand way of
  writing the element
• Where a one letter symbol is used, it is written
  in upper case
• Where two letters are used, the first is written
  in upper case, and the second in lower case

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Atomic Symbols continued

• Some element symbols are clearly abbreviations of
  the elements names e.g. carbon C, oxygen O,
  calcium Ca
• Others, such as iron Fe, sodium Na, mercury
  Hg, are abbreviations of their Latin names
  ferrum, natrium and hydrargyrum

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Atomic Number

• Each element has a different ATOMIC NUMBER this
  is identified at the top of their square

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Al
26.981
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Abundance of the Elements

• ABUNDANCE means how much there is of it.
• There are differences between the abundance of
  elements in the Universe, the Earth and in the
  human body.

All other elements 3
Hydrogen 60
Helium 37
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All other elements mainly metals 12
Oxygen 47
Iron 5
Aluminium 8
Silicon 28
Calcium 2
All other elements mainly metals 2
Nitrogen 2
Hydrogen 10
Oxygen 65
Carbon 18