3. Atoms need a full valence shell to be stable “happy”

4. Chemical Bonds / Formulas  Atoms bond with other atoms to become stable or “happy” – octet rule (full valence shell – 2 in first energy level or 8 in second energy level)  When the atoms bond they form compounds.  Each compound has a special formula

5. Chemical Formulas MgCl 2  Formula has element symbols and subscripts.  Subscripts show how many of each element is in the compound  The subscript is the number at the bottom of a formula.  There is 1- Mg & 2 – Cl  Never use 1 as a subscript!

6. IONIC BOND transfer of electrons resulting in a bond formed between metal ion & nonmetal ion

7. Ions  Atom that gains or loses (transfers) electrons to become stable “happy”  Cation: metals; loses e- to form (+) charged ion  Anion: nonmetals; gains e- to form (-) charged ion

8. Take a moment to write ion charges for the representative groups on YOUR periodic table.

9. Formation of ionic bonds Ionic compounds result when metals react with nonmetals The ionic bond is formed by the ELECTROSTATIC ATTRACTION between the (+) and (-) charges

11. Rules Naming & Writing Ionic Formulas Two types of Ionic Bonds Binary – 2 elements Ternary – more than 2 elements

12. Writing Binary formulas: using representative metals (s&p block) 1. Write the representative metal ion 2. Write the representative nonmetal ion 3. Look at charges to find subscripts If charges cancel (same number just opposite charges) – ratio is 1:1 (write one of each) If charges DO NOT cancel – drop & swap (numbers not the charges)

13. Practice Writing Binary Formulas - using representative metals  Calcium & Oxygen Ca +2 O -2 CaO  Magnesium & chlorine Mg +2 Cl – MgCl 2

14. Writing Binary formulas: using transition metals – d & f block  Ion charges of transition metals change – an element can have more than one ion charge  Use the same steps as binary representative using the transition charge given.  The charge is given as a ROMAN NUMERAL Ex: Iron (II) Fe +2 / Iron (III) Fe +3 Gold (I) Au + / Gold (III) Au +3

15. Practice Writing Binary Formulas - using transition metals  Iron(II) & Oxygen Fe +2 O - 2 FeO  Iron (III) & chlorine Fe +3 Cl – FeCl 3

16. Practice  Magnesium & iodine  Silver(I) & nitrogen  Barium & nitrogen  Gold(III) & phosphorus

17. Roll the Dice 1. Make a stack of metals & nonmetals. (don’t forget the transition metal cards with Roman Numerals) 2. Flip both stacks over – face down. 3. Flip over one metal card & one nonmetal card – face up. 4. Write the cation (metal) and anion (nonmetal) in the columns on handout and put the cards to the side. 5. Using the charges, write the formula. 6. Complete 1-15

18. Naming Binary Formulas  Representative Metals Name the metal Change the ending of the nonmetal to – ide MgCl 2 - magnesium chloride AlP - aluminum phosphide Cl – chloride C - carbide F – flouride Se - selenide I – iodide N – nitride P – phosphide S – sulfide Br – bromide O – oxide  Transition Metals Name the metal & Include the charge using a Roman Numeral Ex: Iron (II) Fe +2 / Iron (III) Fe +3 Gold (I) Au + / Gold (III) Au +3 Change the ending of the nonmetal ending to –ide Fe +2 Cl - iron (II) chloride Au + O -2 gold (I) oxide

19. Practice  CaBr 2  Na 3 N  BCl 3  MgO  FeCl 3  Ni 3 N  ZnO  FeS

20. Roll the Dice 1. Write the name for all the formulas on your sheet. (Be sure to ask me for help) 2. Once those are complete – flip your sheet and complete the back. 3. Once that is complete – turn it in.

21. Ternary Ionic Bonds (more than 2 elements) contain Polyatomic Ions  Polyatomic ion : a group of (covalently) bonded nonmetals that form a charge.  Act as a single ion in an ionic bond  Have special names that DO NOT CHANGE  You need to write down the polyatomic ions and their names on a separate sheet of paper!!!  You will use your list on all quizzes and tests!

22.  AmmoniumNH 4 +  AcetateC 2 H 3 O 2 -  HypochloriteClO -  ChloriteClO 2 -  ChlorateClO 3 -  PerchlorateClO 4 -  CyanideCN -  HydroxideOH -  NitriteNO 2 -  NitrateNO 3 -  Bicarbonate/Hydrogen Carbonate HCO 3 - Carbonate CO 3 -2 Chromate CrO 4 -2 Dichromate Cr 2 O 7 -2 Oxalate C 2 O 4 -2 Sulfate SO 4 -2 Sulfite SO 3 -2 Phosphite PO 3 -3 Phosphate PO 4 -3 Permanganate MnO 4 - Peroxide O 2 -2

23. Writing Ionic Formulas ternary ionic 1. Write the cation – all metals ( only polyatomic cation is ammonium: NH 4 + ) 2. Write the anion – all nonmetals and polyatomic ions 3. If charges cancel – 1:1 ratio 4. If charges DO NOT cancel – drop & swap You must use parenthesis if more than one polyatomic ion is present

24. Practice  cesium nitrate  barium sulfite  aluminum hydroxide  strontium phosphate  ammonium sulfide  Iron(III) chlorite  Zinc(II) nitrite  Gold(III) carbonate  Silver(I) phosphite  Copper(I) acetate

25. Naming ternary ionic formulas - Representative metal  Name the cation  Use the same name for the polyatomic ion  If the anion is a nonmetal – change the ending to -ide Transition metal  Name the metal and include a ROMAN NUMERAL for the charge of the metal  Use the same name for the polyatomic ion  If the anion is a nonmetal – change the ending to -ide

26. Practice Ionic All – write the name and formula for each  Manganese (IV) nitride  CuCl 3  Ammonium carbonate  FeSO 3  Potassium sulfide  K 3 PO 4  Gold(III) hydroxide  Sr(HCO 3 ) 2

27. COVALENT BOND bond formed by the sharing of electrons

28. Covalent Compounds Covalent compounds result when nonmetals react with nonmetals Both nonmetals share their valence electrons to be happy – Octet Rule Examples: CO 2 SCl 2 H 2 OCH 4

29. Naming Covalent formulas  Use prefixes to show the # of atoms of each element in a covalent compound  1 – mono 6 - hexa  2 – di 7 - hepta  3 – tri 8- octa  4 – tetra9 - nona  5 – penta10 – deca  1 st element – use prefixes only of the # of atoms is greater than 1  2 nd element – use prefixes; change ending to – ide

30. Practice  CO 2  N 3 F 8  Se 4 Br 9  S 7 O tetraselenium nonabromide trinitrogen octaflouride heptasulfur monoxide carbon dioxide

31. Writing Covalent formulas  Use the prefix to identify how many of each nonmetal atoms are in each molecule  The prefix becomes the subscript. Carbon TetrahydrideDisulfur Hexachloride ○ CH 4 S 2 Cl 6

32. 1)Name the following covalent compounds: a)SiF 4 b)N 2 S 3 c)H 3 Br 7 d)S 5 Br 9 e) H 2 O 2)Write the formulas for the following covalent compounds: a)diboron hexahydride b)nitrogen tribromide c)sulfur hexachloride d)diphosphorus pentoxide

34. Properties of IONIC BONDS  Form a network of ions. – very strong bonds.  Conduct electricity when melted or dissolved in water.  Mostly solids

35. Properties of COVALENT BONDS  Weak Bonds – easily broken  Usually gases or liquids (CO 2 H 2 O CH 4 )  Not good conductors of heat or electricity

36. Lewis Structures  Element symbol that also indicates number of valence electrons  Practice: Na Sr Al C P O Cl

37. How ionic bonds form  Transfer of ve- to form charges CaCl 2 1. Draw lewis structures for all elements 2. Show transfer with an arrow 3. Resulting in charges 4. Form formula

38. How covalent bonds form  Sharing of ve- H 2 O 1. Draw Lewis Structures for all elements 2. Match up unpaired electrons (circle) this creates a bonded pair (line) 3. Rewrite with paired and bonded pairs

39. Types of Covalent Bonds Nonpolar Covalent – nonmetals have an EVEN sharing of electrons. Ex: Diatomic Molecules – 2 of the same nonmetals bonded to each other (H 2 N 2, O 2, F 2, Cl 2, Br 2, I 2 ) Polar Covalent – nonmetals have an UNeven sharing of electrons. Identified by the nonmetals’ electronegativity

40. Covalent Bonds Covalent bonds are made by SHARING electrons

41. Drawing Covalent Bonds 1. Looking at the formula, draw the Lewis Structure for both nonmetals. 2. Pair all unpaired electrons in each nonmetal to each other. 3. Represent the shared pair of electrons (2e-) with a line. -