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Early Periodic Table. 1700’s about 30 elements listed. Mostly metals used for constructive purposes, with a few non-metals. Early Periodic Table. J. W. Dobereiner (Early 1800’s) formed groups of 3 called “triads”. Properties of the “middle” element are roughly the average of the other two.
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Early Periodic Table • 1700’s about 30 elements listed. • Mostly metals used for constructive purposes, with a few non-metals.
Early Periodic Table • J. W. Dobereiner (Early 1800’s) formed groups of 3 called “triads”. • Properties of the “middle” element are roughly the average of the other two [http://www.bbc.co.uk/schools/gcsebitesize/img/gcsechem_10.gif]
Early Periodic Table • J. A. R. Newlands (1865) organized all the elements by atomic mass. • Properties repeated every 8 atoms. (musical octaves!) [http://www.bbc.co.uk/schools/gcsebitesize/img/gcsechem_10.gif]
Early Periodic Table • Mendeleev (1869) publishes 1st “Periodic Table” • The table is arranged so that elements in columns have similar properties. [http://jchemed.chem.wisc.edu/Journal/Issues/2003/Aug/Images/JCE2003p847fig3.gif]
[http://www.dlt.ncssm.edu/TIGER/diagrams/periodic/MendeleevPrediction.gif][http://www.dlt.ncssm.edu/TIGER/diagrams/periodic/MendeleevPrediction.gif] The Mendeleev Song
Early Periodic Table • Moseley (early 1900’s) develops the Periodic Law that arranges elements by atomic number.
Early Periodic Table • Periodic Law – When elements are arranged in increasing atomic number, their physical and chemical properties show a periodic pattern. Click Here for The Dynamic Periodic Table
The Periodic Table Today • Groups – Each vertical column of the periodic table, also known as families. [http://www.chem4kids.com/files/art/elem_pertable3.gif]
The Periodic Table Today • Periods – This is each horizontal row of the periodic table. [http://www.chem4kids.com/files/art/elem_pertable3.gif]
The Periodic Table Today • Metals – left of “zig-zag” • Nonmetals – right of “zig-zag”
[http://www.chem.gla.ac.uk/teaching/GenChemWeb/assets/PeriodicTable/PTblMk2/PTblGroups.gif][http://www.chem.gla.ac.uk/teaching/GenChemWeb/assets/PeriodicTable/PTblMk2/PTblGroups.gif]