1. Elements in the same group have what in common? Agenda for Tuesday Jan 4 th 1. Reactivity Lab

2. What is the difference between an element and compound? Agenda for Wednesday Jan 5 th 1.Compounds/molecules 2.Ions

3. Formulas Elements and Symbols – Sodium = Na – Carbon = C Formulas – shows how many atoms of each element is in a substance –H2O–H2O – 5 CO 2

4. Formula Weight Total weight for a molecule – Add the atomic weights of all atoms in the molecule together H2OH2O H = 1.0079 *There are 2 H’s so we multiply by 2 O = 15.99994 5 CO 2

5. What is the total weight for 2 NO 2 ? Agenda for Thursday Jan 6 th 1. Ions and charges

6. Charge on an atom Atoms have a neutral charge Why? – The number of electrons (negative charges) cancel out the number of protons (positive charges)

7. Ions Ion – an atom that loses OR gains electron(s) A Cation is an atom that has lost an electron – positive (+) charge An Anion is an atom that has gained an electron – negative (-) charge

9. Ions If Sodium loses an electron what is its charge? – Lose a negative = positive If Chlorine gains an electron what is its charge? How do we know which atoms will lose and gain electrons?

10. Charges on atoms Use the periodic table to predict charge on an atom Oxidation Numbers - charges +1 +3+4 -3-2 +2

11. Practice Oxidation Numbers KLiSi CaNaH MgCBe ClAlI PF NNe BBr OS

12. Charges MgCl 2 What is the charge of the Magnesium atom? What is the charge of the Chlorine atoms? Find the charges of each atom and the overall charge for : Na 2 S The overall charge always equals 0!!

13. Practice Zero Net Charge How many of each atom do you need to balance (create a zero net charge)? Na + and Cl - K + and N 3- Li + and S 2- K + and O 2- K + and C 4- S 2- and B 3+

14. Find the charge of each atom and the overall charge of KCl Agenda for Friday Jan 7 th 1.Quiz 2.Finish activity 3.Ionic and covalent compounds

15. Define ion, cation, anion Agenda for Monday Jan 10 th 1.Bonds 2.Ionic/covalent practice

16. Binary Compounds Binary compound = one that is composed of two elements

17. Octet Rule Octet = set of 8 Atoms want 8 e - around them when they form compounds. Noble gases are unreactive because they already have 8 e -

18. Octet Rule Atoms of some non-metals tend to gain or share electrons with another non-metal to have a complete octet Ex. Cl 2

19. Ionic Bonding Metal bonds with a non-metal Composed of a cation and an anion – Electrically neutral compound One atom gives its electron(s) to the other atom to form an ionic bond – Bond results from the force of attraction between the opposite charges of the atoms

20. Ionic Bonding Example: Potassium Chloride – K gives one electron to I

22. Ionic Bonds Properties – Crystalline solids (crystal lattice) – High melting points – Conduct electric current – Stronger than covalent NaCl crystal lattice

23. Charges on atoms Use the periodic table to predict charge on an atom Oxidation Numbers - charges +1 +3+4 -3-2 +2

24. Rules for writing Ionic formulas 1.The metal comes first (this does not include hydrogen), non-metal comes second. 2.Find the oxidation number of each element 3.The oxidation number of the metal becomes the subscript number of the non-metal and vise versa. Lithium nitride: Li 1+ and N 3- Li 3 N 1 or Li 3 N

25. Writing Ionic formulas Na 1+ F 1- K 1+ S 2- aluminum sulfide magnesium phosphide Aluminum bromide

26. Rules for Naming Ionic formulas 1.Write the name of the positive ion (metal). 2.If you have a transition metal then you need to figure out its charge (remember the compound’s oxidation numbers must equal 0) and put it in roman numerals after the name; e.g. Copper (II). If it is not a transition metal proceed to step 3. 3.Write the root of the non-metal’s name (chlor- for chlorine, ox- for oxygen). 4.Add the ending –ide to the root.

27. OxygenOxidePhosphorusPhosphide NitrogenNitrideSulfurSulfide Subscripts do not become part of the name for ionic compounds but they are used to determine the charges of the metals that have more than one oxidation number.

28. Naming Ionic Compounds NaCl CaCl 2 FeO

29. Agenda for Tuesday Jan 11 th 1.Metallic Bonds 2.Covalent bonds

30. Metallic Bonding Composed of closely packed cations Valence e - are a “sea of electrons” Attraction between valence e - and cations

31. Metallic Bonding “sea of electrons” model explains physical properties of metals – Good conductors – e - flow freely – Ductile – malleable – luster

32. Covalent Bonding Nonmetal + nonmetal share electrons – Can share more than one pair (double, triple bond) Atoms held together by sharing electrons are covalently bonded

33. Covalent (Molecular) Bonds Properties – Molecules – Lower melting and boiling points – Most are liq or gas – Nonconductors – Start to talk about shapes of molecules Ammonia molecule

34. Multiple Bonds Double and triple covalent bonds – Sharing more than one pair of e - Carbon dioxide Nitrogen Triple bonds are stronger than double bonds – More energy needed to break 3 bonds than 2 bonds

35. Polar and Nonpolar Covalent bonding can be: a)Polar – electrons not shared equally b)Nonpolar – electrons shared equally

36. Drawing Covalent Compounds Draw Dot structure for each compound Pair unpaired electrons of each compound Draw a line where you paired electrons

37. Prefixes Number of atoms PrefixNumber of atoms Prefix 1Mono6Hexa 2Di7Hepta 3Tri8Octa 4Tetra9Nona 5Penta10Deca

38. Naming Covalent Compounds 1 st word: Give the prefix designating the number of atoms of the first element present, then write the element’s name. 2 nd word: Give the prefix designating the number of atoms of the second element present. CO 2 : carbon di Name the root of the second element. CO 2 : carbon di ox Add – ide to the root of the second element. CO 2 : carbon diox ide (official name)

39. Practice N 2 O 4 PCl 5 NO CCl 4 SCl 2 Dinitrogen Tetroxide Phosphorus Pentachloride nitrogen monoxide – or nitrogen oxide Carbon Tetrachloride Sulfur Dichloride

40. More Practice Sulfur Hexafluoride Pentanitrogen Heptoxide Diodine tetrachloride Triastatine Octoxide Phosphorous Mononitride SF 6 N 5 O 7 I 2 Cl 4 At 3 O 8 PN

41. Bonding 100% ionic 100% covalent polar covalent ionic and covalent NaCl NaNO 3 Cl 2 KBr Br 2

42. Agenda for Wednesday Jan 12 th 1. Polyatomic ions

43. Polyatomic Ions Groups of covalently bonded atoms that have lost or gained electrons