Jan 03, 2016
•Late 18th century: Lavoisier's list of 28 elements
•Early 19th century: John Dalton's list of approximately 60 elements
•Döbereiner's "triads" of elements with related or similar properties; e.g., Ca, Sr and Ba
•John Newlands "octaves" or groups of eight elements after which properties seemed to repeat
German chemist who, independently of Dmitri Mendeleev, developed a periodic classification of the chemical elements. Though originally educated as a physician, he was chiefly interested in chemistry and physics.
(Julius) Lothar Meyer (1830 – 1895)
I. II. III. IV. V. VI. VII. VIII. IX. B=11,0 Al=27,3 -- ?In=113,4 Tl=202.7 -- -- -- C=11,97 Si=28 -- Sn=117,8 Pb=206,4 Ti=48 Zr=89,7 -- N=14,01 P=30,9 As=74,9 Sb=122,1 Bi=207,5 V=51,2 Nb=93,7 Ta=182,2 O=15,96 31,98 Se=78 Te=128? -- Cr=52,4 Mo=95,6 W=183,5 -- F=19,1 Cl=35,38 Br=79,75 J=126,5 -- Mn=54,8 Ru=103,5 Os=198,6 ? Fe=55,9 Rh=104,1 Ir=196,7
Co=Ni=58,6
Pd=106,2 Pt=196,7
Li=7,01 Na=22,99 K=39,04 Rb=85,2 Cs=132,7 --
Cu=63,3 Ag=107,66
Au=196,2
?Be=9.3 Mg=23,9 Ca=39,9 Sr=87,0 Ba=136,8 -- Zn=64,9 Cd=111,6 Hg=199,8
DIM
ITR
I MEN
DEL
EEV
(183
4-19
07)
Began working on his periodic table of the elements in the late 1860s.
Arranged the known 63 elements by their atomic weights and organized them into groups possessing similar properties.
Where there were gaps, he correctly predicted the properties for the undiscovered elements (gallium, scandium and germanium).
Established the concept of atomic numbers.
Henry Moseley (1887-1915)
Showed that the ordering of the wavelengths of the x-ray emissions of the elements coincided with the ordering of the elements by atomic number(1913).
Developed periodic table based on atomic number.
PERIODIC LAW
PROPERTIES OF ELEMENTS
ARE PERIODIC FUNCTIONS
OF THEIR ATOMIC NUMBERS
in 1951, Seaborg was awarded the Nobel Prize in chemistry for his work. Element 106 has been named seaborgium (Sg) in his honor.
GLENN SEABORG (1912-1999)
starting with plutonium in 1940, he discovered all the transuranium elements from 94 to 102
reconfigured the periodic table by placing the actinide series below the lanthanide series
THE MODERN PERIODIC TABLE OF ELEMENTS
Properties of Major Divisions
Metals
lusterous, shiny typically solids at room
temperature (except Hg) good conductors of heat and
electricity malleable and ductile tend to lose electrons easily (form
cations)
Properties of Major Divisions
Nonmetals do not have a metallic luster poor conductors of heat and
electricity may be solid, liquid or gas at
room temperature (majority are gases)
not malleable, not ductile tend to gain electrons (form
anions)
Properties of Major Divisions
Semi-metals (metalloids)have properties that are
intermediatebetween metals and nonmetals.
Elmsley, John, The Elements,3rd Ed., Clarendon Press, Oxford,1998.
Chemistry: Connections to Our Changing World, LeMay, et al., Prentice Hall, 1996.
http://www.britannica.com/bcom/eb/article/5/0,5716,53705+1+52397,00.html
http://www.crosswinds.net/~smarsden/unit04/l6u4.htmhttp://www.thirteen.org/archive/hawking/cosmostar/html/cstars_mendel.html
http://www.sweethaven.com/chemele/pertab01.html