Post on 16-Dec-2015
Periodic Table HistoryPeriodic Table History• Dmitri Mendeleev
(1869)• Creates periodic
table with elements listed in increasing mass.
• Finds that properties repeat in the table.
[http://www.stamprussia.com/463b.jpg]
[http://web.fccj.org/~ethall/2045/ch5/pt1871.gif]
[http://www.dlt.ncssm.edu/TIGER/diagrams/periodic/MendeleevPrediction.gif]
Periodic Table HistoryPeriodic Table History
•Henry Moseley (1913) •Current periodic table which
lists in order of atomic number, from smallest to largest.
The Periodic TableThe Periodic Table
[http://www.theschemata.com/gifconventional/17table.gif]
The Periodic TableThe Periodic Table
The Periodic TableThe Periodic Table
•Periods – Each horizontal row of the periodic table.
[http://www.chem4kids.com/files/art/elem_pertable3.gif]
The Periodic TableThe Periodic Table•Groups – Each
vertical column of the periodic table, also known as families.
•Elements in a group have similar properties.
[http://www.chem4kids.com/files/art/elem_pertable3.gif]
The Periodic Table & The Periodic Table & ElectronsElectrons
•The shape of the periodic table is due to where the electrons are located in an atom.
[http://www.bpc.edu/mathscience/chemistry/images/periodic_table_of_elements.jpg]
Nothing here???
The Periodic Table & The Periodic Table & ElectronsElectrons
•“Blocks” of the periodic table represent the last type of cloud that electrons occupy.
[http://wps.prenhall.com/wps/media/objects/476/488316/Instructor_Resources/Chapter_09/FG09_17.JPG]
“S” Cloud
[http://wps.prenhall.com/wps/media/objects/476/488316/Instructor_Resources/Chapter_09/FG09_29.JPG]
“S” Cloud
“P” Clouds
The Periodic Table & The Periodic Table & ElectronsElectrons
•Electron Configurations show where electrons are located in an atom.
•Example: H is 1s1
Period #
Cloud Type
# of Electrons
The Periodic Table & The Periodic Table & ElectronsElectrons
[http://wps.prenhall.com/wps/media/objects/476/488316/Instructor_Resources/Chapter_09/FG09_28.JPG]
Example: Oxygen 1s2 2s2 2p4 (e- = 8)
[http://wps.prenhall.com/wps/media/objects/476/488316/Instructor_Resources/Chapter_09/FG09_28.JPG]
Example: Magnesium 1s2 2s2 2p6 3s2 (e- = 12)
The Periodic Table & The Periodic Table & ElectronsElectrons
•Valence Electrons are the “outside” electrons in an atom
•Highest period number = Highest energy level
The Periodic Table & The Periodic Table & ElectronsElectrons
• Or you could look at the group number…
• Silicon has 4 valence electrons
The Periodic Table & The Periodic Table & ElectronsElectrons