Unit 4 The Periodic Table Chemistry I Mr. Patel SWHS
Topic Outline Continue Learning Major Ions Organization of the Periodic Table (6.1) Classification of Elements (6.1) Tour of the Periodic Table (6.2) Periodic Trends (6.3)
Organizing the PT Properties of elements are used to sort them Mendeleev – 1 st periodic table – Arranged elements based on atomic mass – Made predictions of new elements
Organizing the PT Modern periodic table arranges elements based on atomic number Periodic Law: repetition of physical and chemical properties
Metals Most elements Good conductors, high luster, ductile, malleable Most are solid (except Hg) Found left of stair-step line
Nonmetals Contains the gaseous elements Mostly gas, few solids at room temp Poor conductors Brittle Found to right of stair-step line
Metalloids/Semimetals Properties of metals and nonmetals – Based on physical conditions Found above and below stair-step line
Periodic Table Each block gives information about the element Groups – columns Periods – rows Representative Elements – Groups 1A to 7A
1 H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc (98) 44 Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po (209) 85 At (210) 86 Rn (222) 87 Fr (223) 88 Ra (226) 89 Ac Rf (261) 105 Db (262) 106 Sg (263) 107 Ns (264) 108 Hs (265) 109 Mt (268) 110 Ds (281) 111 Rg (272) 112 Uub (285) 58 Ce Pr Nd Pm (145) 62 Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U Np (237) 94 Pu (244) 95 Am (243) 96 Cm (247) 97 Bk (247) 98 Cf (251) 99 Es (252) 100 Fm (257) 101 Md (258) 102 No (259) 103 Lr (260) Atomic Number Element symbol Weighted average atomic mass 63 Eu Groups Periods
Group 1A Called the Alkali Metals Elements: Li, Na, K, Rb, Cs, Fr (largest atom) Very reactive with air and water Form Bases (alkali)
Group 2A Called the Alkaline-Earth Metals Elements: Be, Mg, Ca, Sr (pic), Ba, Ra Abundant in Earth Crust Reactive with water - bases
Group 7A Called Halogens Elements: F, Cl, Br, I, At Form salts
Group 8A Called Noble Gases Elements: He, Ne, Ar, Kr (pic), Xe, Rn Full electron shell Not Reactive Gases
The Middle Ones Elements between 2A and 3A Transition metals – colors Inner Transition metals at bottom of Periodic Table – Synthetic /Radioactive
IA IIA IIIA IVA VA VIA VIIA VIIIA IIIB IVB VB VIB VIIB VIIIB IB IIB Alkali metals Alkaline earth metals Noble gases Halogens Transition metals Lanthanoids Actinoids Inner Transition metals Groups Periods The Periodic Table of Elements
Periodic Trends Based on the organization of PT, trends in atomic parameters exist – Atomic Size – Ionization Energy – Electronegativity
Atomic Size Atomic Radius – one half the distance between two nuclei when joined (same element)
Atomic Size Trend
Atomic Size Atomic size: – Increases down a column – Decreases across a period Increasing Atomic Size
Ionization Energy Ionization Energy (IE) – energy required to remove an electron from an atom
First Ionization Energy Trend
First Ionization Energy Ionization Energy: – Decreases down a column – Increases across a period Increasing Ionization Energy Increasing IE
Electronegativity Electronegativity – ability of an atom to attract/pull electrons
Electronegativity Trend
Electronegativity Electronegativity: – Decreases down a column – Increases across a period Increasing Electronegativity Increasing EN
Trend Summary Atomic Size Ionization Energy Electronegativity
Which is the larger atom? 1.Be or F 2.Ca or Ba 3.Rb or Cl 4.Largest atom? 1.Be 2.Ba 3.Rb 4.Fr
Which has higher IE? 1.Be or F 2.Ca or Ba 3.Rb or Cl 1.F 2.Ca 3.Cl
Which has higher Electronegativity? 1.Be or F 2.Ca or Ba 3.Rb or Cl 4.Highest EN? 1.F 2.Ca 3.Cl 4.F