Chemistry Chapter 5&6

1. Chemistry Chapter 5&6 The Periodic Law Notes 5

2. Mendeleev’s Periodic Table Dmitri Mendeleev

3. Modern Russian Table

4. Chinese Periodic Table

5. Stowe Periodic Table

6. A Spiral Periodic Table

7. Triangular Periodic Table

8. “Mayan” Periodic Table

9. Orbital filling table

10. Periodic Table with Group Names

11. The Properties of a Group: the Alkali Metals • Easily lose valence electron • (Reducing agents) • React violently with water • Large hydration energy • React with halogens to form salts

12. Sublevel Blocks of the Periodic Table Figure 5-5 p. 129

13. s-block Group 1 Alkali Metals ns1 is highest level Silvery appearance Soft—cut with knife Highly reactive—never found free in nature Low melting points <100oC Group 2 Alkaline-earth metals ns2 is highest level Harder & denser, w/ higher melting points than Group 1 Highly reactive—never found free in nature

14. Special exceptions to s-block Hydrogen Has ns1 Totally different properties from alkali metals Helium Has ns2 Highest level is completely full Stable like noble gases

15. d-block d sublevel for preceding energy level is filling d sublevel filling has some deviations—Group 11: Cu, Ag, Au Outer s & d sublevels still have same # e- Transition elements: d-block metals w/ typical metallic properties Less reactive than Group 1 & 2 Exist free in nature Good conductors of electricity High luster (shiny)

16. p-block All elements of Groups 13-18 except Helium Properties vary greatly Nonmetals (right hand end) All six metalloids Brittle solids Some properties of metals and nonmetals Eight metals (left hand side and bottom of the block) Harder and denser then s-block alkaline-earth metals Softer and less dense than d-block metals Stable in the presence of air Group 17 Halogens Most reative of the nonmetal 7 electrons in outer shell

17. f-block Lanthanides & Actinides 14 elements—seven 4f orbitals are filling Lanthanides Similar reactivity to Group 2 Shiny metals Actinides Only 1st four found in nature All are radioactive

18. Determination of Atomic Radius: Half of the distance between nucli in covalently bonded diatomic molecule "covalent atomic radii" Periodic Trends in Atomic Radius • Radius decreases across a period Increased effective nuclear charge due to decreased shielding • Radius increases down a group Addition of principal quantum levels

19. Table of Atomic Radii

20. Ionization Energy - the energy required to remove an electron from an atom • Increases for successive electrons taken from • the same atom • Tends to increase across a period Electrons in the same quantum level do not shield as effectively as electrons in inner levels Irregularities at half filled and filled sublevels due to extra repulsion of electrons paired in orbitals, making them easier to remove • Tends to decrease down a group Outer electrons are farther from the nucleus

21. Ionization of Magnesium Mg + 738 kJ  Mg+ + e- Mg+ + 1451 kJ  Mg2+ + e- Mg2+ + 7733 kJ  Mg3+ + e-

22. Table of 1st Ionization Energies

23. Another Way to Look at Ionization Energy

24. Electron Affinity - the energy change associated with the addition of an electron • Affinity tends to increase across a period • Affinity tends to decrease as you go down • in a Group or family Electrons farther from the nucleus experience less nuclear attraction Some irregularities due to repulsive forces in the relatively small p orbitals

25. Table of Electron Affinities

26. Ionic Radii Cations • Positively charged ions • Smaller than the corresponding • atom Anions • Negatively charged ions • Larger than the corresponding • atom

27. Summation of Periodic Trends

28. Table of Ion Sizes

29. Electronegativity A measure of the ability of an atom in a chemical compound to attract electrons • Electronegativities tend to increase across • a period • Electronegativities tend to decrease down a • group or remain the same

30. Periodic Table of Electronegativities