History of the Periodic Table

“Early chemists describe the first dirt molecule.”

Antoine Lavoisier Compiled a list of all the known elements of the time (1790’s)

Text p 174

John Newlands (1864) Noticed repeating patterns “Law of octaves”

Stanislao Cannizzaro Developed an accepted method for measuring atomic mass

Dmitri Mendeleev Noticed repeating properties of elements – “Periodicity” Published his periodic table in 1869 Left gaps in table – Predicted properties of undiscovered elements

Dmitri Mendeleev Noticed some inconsistencies in properties and atomic mass Left them alone – He believed properties were more important than atomic mass

Henry Moseley (1913) Developed concept of atomic number Arranged elements by increasing atomic number Explained inconsistencies in Mendeleev’s table

The Periodic Law The physical and chemical properties of elements are periodic functions of their atomic numbers

The Modern Periodic Table

Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Important Types of Elements

Metals and Nonmetals Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Metals Very good conductors of heat and electricity Usually shiny and malleable

Metals Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Nonmetals Very poor conductors of heat and electricity – “Nonconductors” Exist in all three phases Usually dull and brittle when solid

Nonmetals Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Metalloids Have some properties of both metals and nonmetals – “semi-metals” Slightly conductive Usually dull, brittle solids

Metalloids Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Electron “Blocks” s-block p-block d-block f-block

Ge Sn Pb As Sb Bi Se Te Po Br I At Xe SiPSCl CNOF Li K Cs Fr Be Sr “Representative” or “Main Group” Elements Na Rb Mg Ca Ba Ra Ga In Tl Kr Rn 113 AlAr BNe He H

Important Families of Elements

Alkali Metals (“s” block) (Group 1) Very reactive – Not found as free metals in nature – React vigorously with water and with many nonmetals Soft, silvery metals Fairly low melting points

Group 1: Alkali Metals Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Alkaline-Earth Metals (“s” block) (Group 2) Reactive, but not as reactive as alkali metals – Not found as free metals in nature Harder, denser, and higher melting points than alkali metals

Group 2: Alkaline Earth Metals Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr H

Transition Metals (“d” block) Harder, denser than alkali or alkaline-earth metals Much higher melting points than alkali or alkaline-earth metals (except for Hg) Much less reactive Brightly-colored compounds

Groups 3-12: The Transition Metals H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr

“p-block” Elements Wide variety of properties – All of the nonmetals – All of the metalloids – All of the noble gases – Some metals – All three physical states

“p-block Elements” H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr

Halogens (Group 17) Most reactive nonmetals React vigorously with most metals to form salts All three physical states

Group 17: The HalogensH Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr

Noble Gases Group 18 Very unreactive – Used to be called “inert” gases

Group 18: The Noble Gases H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr

Hydrogen and Helium Odorless, colorless gases Hydrogen is placed in Group 1 because of its 1s 1 electron configuration Helium is placed in group 18 – Helium is unreactive – Its 1s 2 configuration completely fills its only main energy level

H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr Hydrogen and Helium

Inner Transition Metals (“f” block) Lanthanide series and Actinide series No groups-they are in between Groups 3 and 4 Lanthanides (Period 6) – “Rare earths” – Shiny, reactive metals Actinides (Period 7) – Unstable, radioacative elements – Most are synthetic

H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr Inner Transition Metals

The Lanthanides (Rare Earths) H Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr

The ActinidesH Li Na K Rb Cs Fr Be Mg Ca Sr Ba Ra Sc Y La Ac Ti Zr Hf 104 V Nb Ta Cr Mo W Mn Tc Re Fe Ru Os Co Rh Ir Ni Pd Pt Cu Ag Au Zn Cd Hg Ga In Tl Ge Sn Pb As Sb Bi Se Te Po Br I At Kr Xe Rn AlSiPSClAr BCNOFNe He CePrNdPmSmEuGdTbDyHoErTmYbLu ThPaUrNpPuAmCmBkCfEsFmMdNoLr