Agenda: 10/23

1. Homework: Agenda: 10/23 • Warm-up: Ionic Bonds • Ionic Compounds – names & formulas • Binary • With Roman numerals • With 3 or more elements • Covalent Compounds (molecules)

2. Ionic Bonds (Black Study Guide) • Read

3. Compounds Stable (do not easily change) Most atoms are bonded into compounds Separated with chemical reactions Usually need high heat or electricity

4. Ionic Compounds Metals lose valence electrons Non-metals gain valence electrons

5. Ionic Bonding: Transfer of valence electrons • Ionic bonding occurs when a metal loses 1+ electrons to a non-metal in an effort to attain a stable octet of valence electrons. • Use Electron Dot Diagrams (Lewis diagrams) to show the ionic bonds for one formula unit. • Na Cl = Na⁺¹Cl⁻¹

6. Electron Dot Diagram (Lewis) ClCaCl = CaCl

7. Ionic Compounds Names and Formulas

8. Language of chemistry: Standardize system to represent compounds

10. Ionic Compounds

11. Ionic compounds: Found in minerals and rocks • Granite: rock (combination of minerals)

12. Halite: NaCl • Use as source of table salt

13. Ionic compounds: rocks & minerals Al₂O₃ Aluminum oxide

14. Pyrite (Fool’s gold) Iron sulfide FeS₂ Used to produce sulfuric acid for the chemical industry

15. Ionic Compounds - Opposites Attract • Separate cations and anions to bond • Use only the single element ions (not the polyatomic ions) • Write the symbol and the charge • Write the new compound formed by combining the ions. Write the formula showing that the charges (oxidation numbers) add up to 0 (cancel out) • Name the compound. • Write at least 15 compounds. • Ten should include subscripts.

16. Ionic Compounds: Names & Formulas • The formula for ionic compounds are determined by the charges (oxidation numbers). The overall charge of the compound must equal 0. • The charges are determine by the number of valence electrons that the element loses or gains to reach 8 valence electrons. This is the octet rule that makes the compound stable (does not easily react.)

17. c.Metals always _______ electrons to form a ____ ion. Non-metals always _______ electrons to form a ______ ion .

18. e. Since Aluminum has a charge (oxidation number) of 3⁺, - It must have __________ chlorine atoms (ions) to make a stable compound. -It must have __________ nitrogen atoms (ions) to make a stable compound. -It must have _______ aluminum and ________ oxygen atoms (ions) to make a stable compound.

19. Write the correct formula for compounds composed of: Sodium and bromine Sodium and sulfur Sodium and phosphorus Calcium and bromine Calcium and sulfur Calcium and phosphorus

20. Names for Ionic compounds • Rules for naming: • Metals are written first. • Non-metals change their name to an “-ide” ending. • Prefixes are ________ ___________.

21. Ionic Compounds- Formulas Salt is a commonly used term for all ionic compounds

22. Some Ionic Compounds are more complex Include polyatomic ions

23. Ionic compounds: Found in minerals and rocks Barite = BaSO₄ Used to make paper & glass Source of barium used For x-rays of the digestive system

24. Ionic compounds: Found in minerals and rocks Gypsum = CaSO₄· 2H₂O Used for plaster for walls, ceilings, sculptures

25. Ionic compounds: Found in minerals and rocks Calcite = CaCO₃ Used in paint, Antacids, calcium Supplement for food

26. Ionic compound with polyatomic ions Calcium sulfate in casts Barium sulfate to absorb x-rays Acetate uses Sodium acetate In Heat packs

28. Sodium hydrogen carbonate (old name: sodium bicarbonate) Medical: used in emergency situations to correct pH of blood Baking soda: to make cakes rise

29. Bleach Dentistry: Clean and disinfect Root canals Rocket fuels: Source of oxygen

30. POLYATOMIC IONS Examine the names & formulas: What is the pattern? Do they end in “–ide?” Ions with -1 charge perbromate BrO4-1 bromate BrO3-1 bromite BrO2-1 hypobromite BrO-1 perchlorate ClO4-1 chlorate ClO3-1 chlorite ClO2-1 hypochlorite ClO-1 periodate IO4-1 iodate IO3-1 iodite IO2-1 hypoiodite IO-1 nitrate NO3-1 nitrite NO2-1 hydroxide OH-1 cyanide CN-1 thiocyanate SCN-1 acetate C2H3O2-1 Permanganate MnO4-1 bicarbonate HCO3-1 Ions with a -2 Charge carbonate CO3-2 phthalate C8H4O4-2 sulfate SO4-2 sulfite SO3-2 chromate CrO4-2 dichromate Cr2O7-2 oxalate C2O4-2 peroxide O2-2 Ions with a -3 Charge phosphate PO4-3 phosphite PO3-3 arsenate AsO4-3 Ions with +1 charge ammonium ion NH4+1

31. Compounds vs. Polyatomic Ions

33. Polyatomic ions that you must know:

34. Using polyatomic ions: • Sodium + nitrate Calcium + nitrate Formula Name:

35. Writing Formulas (criss –cross method)

36. Ionic Compounds with Transition Metals • The transition metals are elements in Groups _____ to _______. • + post transition metals: under the staircase. • Transition metals can have more than one charge. • Use Roman numerals after the name. • Roman numbers: • I = II = III = IV = V=

38. Transition metals • Examples Iron II oxide Iron III oxide Write the formulas for: Copper I oxide Cobalt III chloride Nickel II sulfide

39. Formula Writing Practice

40. Practice: Writing Binary Formulas • Many transition and post transition metals have multiple oxidation numbers (charges) • Ni: oxidation numbers of _____ & _____ • Fe: • Find other examples: • Write formulas • Write names