Agenda:

1. Agenda: Homework: Objective: To understand the physical and chemical properties of atoms based on their position on the Periodic Table Warm-up: Properties of Groups Trends in properties How do we use the Periodic Table to predict properties of elements? Reactivity: Atomic size Ionization Energy Electronegativity Return Test Next Unit is forming bonds and compounds based on reactivity

2. Warm-up: Properties of Groups • Alkali Metals, Halogens, Noble Gases • Which group is the least reactive? • In Group 1, which elements are most reactive? Why? • In Group 17, which elements are most reactive? Why? • Which Group contains all gases? • Which group always forms ionic compounds? • What other properties change in a Group when going down the PT?

3. Predicting how easily an element reacts What characteristics of an element impact how easily it reacts with other elements to form a chemical compound? The electron arrangement of each atom determines its chemical behavior (how it reacts and bonds). • Forming ions based on number of valence electrons • Atomic size • Ionization energy • Electronegativity

4. Atoms lose, gain or share valence electrons in order to be stable like the Noble Gases. Metals will: Non-metals will:

5. Forming Compounds • Ions come together to form a ______________ ______________ . • Many formula units are held together to make an _______ compound.

6. Periodic TrendsUsing the Periodic Table to predict Properties of Elements and Groups Focus on Reactivity Atomic size Ionization Energy Electronegativity

7. Atomic Radii • Atomic Radius – measurement of the size (volume) of the atom • Defined by the edge of its orbital but since the edges are fuzzy, difficult to determine • Atomic Radii – half the distance between the nuclei of identical atoms that are bonded together

8. Ionization Energy • Ionization energy – the energy required to remove one electron X + energy  X+ + e- • An electron can be removed from an atom if enough energy is absorbed (+) by the atom • Note: measurements of this are made on individual atoms in gas phase to avoid interactions with nearby atoms Adding energy = Endothermic

9. How do metal atoms lose electrons? Ionization energy Ground State, Excited State, Ionization energy Lithium

10. Electronegativty • Electonegativity: An atoms’ ability to attract electrons from another atom • Electron Affinity: The energy released when an electron is added to an atom X + e-  X-+ energy Releasing energy = Exothermic

11. How do non-metal atoms gain electrons? Electronegativity Large non-metal Small non-metal atom atom

12. Examining properties & trends • Use Interactive Periodic Table –http://www.ptable.com/ • Click on Properties • Work in pairs • Each person completes the table • When completed, investigate the properties of the transition metals • Homework: Summary on a separate paper • Define the property • Summarize its trends: across periods and down groups • Summarize the characteristics of the property in each of the 3 groups studies

13. Linking Electron Arrangement to the PT • Use Interactive Periodic Table –http://www.ptable.com/ • Click on Orbitals S P D F blocks Which are being filled?

14. Noble Gas Notation – using the PT

15. Periods ? Rules for Group 1 & Group 2

16. Rules for Groups 13-18 Periods?

17. Rules for Transition Metals Period ?

18. 7. Reactivity Group 18 (called the _______________) are ____________ (also called ________ or _____________), because: Group 1 (called ____________) are the most reactive metals because: Group 17 (called ___________) are the most reactive nonmetals because:

19. Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals 1 18 Reactivity: trends for metals and non-metals

20. Predicting Properties of Elements - based on the position on the Periodic Table : Size; IE; EN Property: which element has the largest value? Ca vs. Br C vs. SnF vs. I Si vs. Cl Na vs. P Li vs. K Be vs. O S vs. Ar Al vs. S Ne vs. Kr B vs. Al B vs. Ne

21. Periodic Trend Animation • http://faculty.ucc.edu/chemistry-pankuch/Amin.html • Atomic size • Ionic size Interactive animations • Ionization • Electronegativity • For later used: bond formation

22. Periodic Table • Objective: To understand the physical and chemical properties of atoms based on their position on the Periodic Table • NC Essential Standards 1.3 • Physical properties: • Chemical properties:

23. Periodic Tables • Groups • Http://www.ptable.com/Images/periodic%20table.png • Interactive Periodic Table – useful for trends of properties • http://www.ptable.com/

24. Periodic TrendsUsing the Periodic Table to predict Properties of Elements and Groups Focus on Reactivity Atomic size Ionization Energy Electronegativity Electron Affinity

25. Atomic Radii • Atomic Radius – measurement of the size (volume) of the atom • Defined by the edge of its orbital but since the edges are fuzzy, difficult to determine • Atomic Radii – half the distance between the nuclei of identical atoms that are bonded together

26. Atomic Radii • Across Period: • atoms get smaller • because of the increased number of protons attracting the electrons • the electrons added in the same energy level do not shield electrons from nuclear charge • Down Group: • atoms get larger • increases • because the energy levels being added to the atom

29. Atomic/Ionic Radii

30. Ionization Energy • Ionization energy – the energy required to remove one electron X + energy  X+ + e- • An electron can be removed from an atom if enough energy is absorbed (+) by the atom • Note: measurements of this are made on individual atoms in gas phase to avoid interactions with nearby atoms

31. Ionization Energy

32. Ionization Energy • Across Period: • requires more energy to remove an electron so increases • because electrons added in the same energy level do not shield electrons from nuclear charge • Down Group: • requires less energy to remove electron so decreases • because the valence electrons are farther away from protons attracting them

33. Ionization Energy

34. Ionization Energy

35. Electronegativty • Ability to attract electrons • Non-metals (excluding Noble Gases) • High electronegativity

36. Electronegativity • Across Period: • Increases • Non-metals attract electrons • Smaller atoms • Down Group: • Decreases • Protons in the nucleus are shielded by inner energy levels • Harder to attract electrons

37. Electronegativity

38. Periodic Trend Animation • http://faculty.ucc.edu/chemistry-pankuch/Amin.html • Atomic size • Ionic size Interactive animations • Ionization • Electronegativity • For later used: bond formation

39. Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals 1 18 Reactivity: trends for metals and non-metals

40. 6. Octet Rule Atoms tend to ______, ______, or _______ electrons in order to have _____ valence electrons. _______ valence electrons gives stability. Exception: Duet rule: Hydrogen

41. 7. Reactivity Group 18 (called the _______________) are ____________ (also called ________ or _____________), because: Group 1 (called ____________) are the most reactive metals because: Group 17 (called ___________) are the most reactive nonmetals because:

42. Trends for Ionization Energy & ElectronegativityArrows to show trends for metals & non-metals 1 18 Reactivity: trends for metals and non-metals

43. Predicting Properties of Elements - based on the position on the Periodic Table : Size; IE; EN Property: which element has the largest value? Ca vs. Br C vs. SnF vs. I Si vs. Cl Na vs. P Li vs. K Be vs. O S vs. Ar Al vs. S Ne vs. Kr B vs. Al B vs. Ne

44. Periodic Table videos • New Periodic Table Song • http://www.youtube.com/watch?v=IsBZx0tv6dQ • Prism website • http://www.gk12.ilstu.edu/chemistry/index.asp?page=periodicTable