Periodic Table Trends PDF

Periodic Table: A systematic catalog of elements. Elements are arranged in order of atomic number.  PERIODIC LAW- “ the physical and chemical properties of the...

Periodic Table: A systematic catalog of elements. Elements are arranged in order of atomic number.  PERIODIC LAW- “ the physical and chemical properties of the elements are periodic functions of their atomic number.”  Periodic properties are: 1-. Atomic size 2. ionization energy 3. electronegativity 4. electron affinity 5. metallic and non metallic property Atomic size (radius), Ionic size (radius), Ionization energy, Electronegativity.  Periodic Properties! Atomic Radius size of atom © 1998 LOGAL  Periodic Trends 250 200 Atomic Radius (pm) 150 100 50 0 0 5 10 15 20 Atomic Number Atomic Radius 250 K 200 Na Atomic Radius (pm) 150 Li 100 50 Ar Ne 0 0 5 10 15 20 Atomic Number Atomic Radius Increases going down and Decreases going right. Decreases! I n 1 c 2 r 3 e a 4 s 5 e 6 s 7 Atomic Radius Why larger going down? Higher energy levels have larger orbitals Shielding - core e- block the attraction between the nucleus and the valence e- Why smaller to the right? Increased nuclear charge without additional shielding pulls e- in tighter  Ionic Radius Ionic Radius Cations (+) lose e- smaller Anions (–) gain e- larger © 2002 Prentice-Hall, Inc. Examples Which atom has the larger radius? Be or Ba Ba Ca or Br Ca Examples Which particle has the larger radius? S or S2- S2- Al or Al3+ Al  Ionization Energy Energy required to remove one e- from a neutral atom. (gaseous state) © 1998 LOGAL Ionization Energy Decreases going down and Increases going right. Increases! D1 e2 c r 3 e4 a5 s e6 s 7 Ionization Energy 2500 He Ne 1st Ionization Energy (kJ) 2000 1500 Ar 1000 500 Li Na K 0 0 5 10 15 20 Atomic Number  Ionization Energy Why opposite of atomic radius? In small atoms, e are close to the nucleus where the attraction is stronger, therefore they are more difficult to remove Which family has the highest IE and why? Examples Which atom has the higher 1st Ionization Energy? N or Bi N Ba or Ne Ne Periodic Properties cont… Electronegativity The tendency for an atom to attract e- to itself when it is chemically combined with another element. Electronegativity Cs = least electronegative (0.7) F = most electronegative (4.0) Noble gases omitted because they do not form many compounds. When F combines with another element, it attracts e- strongly. Tug-of-War!! Electronegativity Electronegativity Decreases going down and Increases going right. 1 2 3 4 5 6 7  Examples Which particle has the higher electronegativity? K or Ca Ca Al or Ga Al Periodic Properties cont… Electron affinity The energy released when an atom accepts electron to itself. Electron affinity Electron affinity Decreases going down and Increases going right. 1 2 3 4 5 6 7  Examples Which particle has the higher electron affinity? K or Ca Ca Al or Ga Al  Metallic & Nonmetallic Properties Metallic elements- those that have the greater ability to lose electrons Increases going down and decreases going right.  Metallic & Nonmetallic Properties Nonmetallic elements- those that have the greater ability to gain electrons to itsef Decreases going down and increases going right. QUIZ: Give the correct answer. 1. The smallest atom- Li, K, F, Cl 2.Biggest atom- Be, Sc, Fe, C 3.has highest IE- Na, Mg, Al, Cl 4. smallest IE- K, Y, W, I 5.highest EN – Na, Mg, Al, Si 6. more electronegative- N. P, As, Sb 7. more energy released- Fe, Al, Co, Mg 8.more metallic- Li, Na, K, Rb 9. more nonmetallic-N, O, F, Cl 10.more ability to lose electron- Au, Ag, Ni, Fe