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