The Periodic Table - Dr. VanderVeendrvanderveen.com/H Periodic Table Intro.pdfDmitri Mendeleev...
Transcript of The Periodic Table - Dr. VanderVeendrvanderveen.com/H Periodic Table Intro.pdfDmitri Mendeleev...
Organizing information… By the mid-1800’s, about 70 elements
were known Similarities of certain elements
Coinage elements: copper, silver, gold Halogens (“salt-maker”): chlorine, bromine,
iodine Alkali metals: lithium, sodium, potassium
Dmitri Mendeleev (1834-1907) 1869—published first
periodic table of the elements
Listed all known elements in order of increasing atomic mass
Dmitri Mendeleev (1834-1907) 1869—published first
periodic table of the elements
Arranged rows so that elements with similar properties were side by side
Dmitri Mendeleev (1834-1907) 1869—published first
periodic table of the elements
Arranged rows so that elements with similar properties were side by side (even if out of order by mass)
Dmitri Mendeleev (1834-1907) Left blanks in table if
no element with appropriate property was known This led to very
accurate predictions of scandium, germanium and gallium
Henry Moseley (1887-1915) Used x-ray
diffraction data on the elements to determine the nuclear charge
Henry Moseley (1887-1915) Used x-ray
diffraction data on the elements to determine the nuclear charge
Realized that the properties of the elements are related to atomic number
Glenn Seaborg Rearranged the
periodic table by putting the lanthanides and actinides under the main body of the table
Video
Modern Periodic Table Groups—vertical
columns Convention #1:
Numbered 1-18 Convention #2: numbers
with A/B Convention #3: number s &
p blocks only
Modern Periodic Table Video Most of the elements in the periodic table
are metals!
Classes of elements Metals Typically solids
Exception: mercury
Lustrous Good conductors Malleable Ductile
Nonmetals May be solid,
liquid or gas Solids are brittle Nonconductors
Group 1—Alkali Metals Most reactive metals Must be stored under oil Not found as free elements in
nature Soft can be cut with a knife
Reactions with water http://www.youtube.com/watch
?v=QSZ-3wScePM
Group 2—Alkaline Earth Metals Less reactive than
alkali metals
Group 2—Alkaline Earth Metals Less reactive than
alkali metals Not found as free
elements in nature
Group 16—Chalcogens Tend to form -2
anions Aka “oxygen
family”
Periodic Videos: Selenium
Group 17—Halogens The most reactive
nonmetals Periodic Videos:
Fluorine
Group 17—Halogens The most reactive nonmetals 7 valence electrons
Tend to form -1 anions Form diatomic molecules
F2, I2, Cl2, Br2
Halogens
Group 18—Noble Gases Non-reactive gases
Open University: Noble Gases Don’t tend to gain or lose
electrons Typically don’t form compounds
The Periodic Law When elements are arranged according
to increasing atomic number, there is a regular and repeating pattern in their chemical and physical properties.