Understanding Chemical Bonding and Compound Formulas in Chemistry

1. Homework: Re-write in paragraph form – notes pages 1 and 3. Add additional information learned in practice. Agenda: 3/17 – 3rd block Objective: To interpret (correctly write) formulas and names for compounds – using IUPAC convention Warm-up: review names & formulas Review: Binary Ionic Compounds More Complex Ionic Compounds With Polyatomic Ions With Transition Metals Covalent Compounds

2. Warm-up: Review names & formulas

3. Language of chemistry: Standardize system to represent compounds

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 or more 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. Some Ionic Compounds are more complex Include polyatomic ions

8. 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

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

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

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

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

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

15. 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

16. Compounds vs. Polyatomic Ions

17. Polyatomic ions that you must know:

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

19. Writing Formulas (criss –cross method)

20. 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=

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

23. Formula Writing Practice

24. 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

25. Language of chemistry: Standardize system to represent compounds

26. Covalent Compounds Molecules Names & Formulas for Inorganic Covalent Compounds

27. Compounds Stable Most atoms are bonded in compounds Separated with chemical reactions Usually need high heat or electricity

28. Earth’s atmosphere

30. Names of Binary Molecules • First-element name • 2nd – end in “ide” • Use prefixes -Always with 2nd element -With 1st element except mono- Element with lowest EN goes first On the Periodic Table – across /down

31. Practice: • Complete the table in your notes. • Write the names • Write the formula

32. Acids • Acids are molecules that are in aqueous solution (_________ in __________) and produce hydrogen ions (H¹⁺) • Typically start with H • Almost act as an ionic compound Electronegativity Difference:

33. Acids: H + Halogen • Hydro + Halogen (ic) + Acid • HBr • Hydrobromic acid

34. Oxyacids: common acids • Contains oxygen (in a polyatomic ion) • Note the endings of the anion & the acid name • H + nitrate = Nitric Acid • H + sulfate = • H + phosphate = • H + acetate =

35. Inorganic covalent compounds

36. 7 Diatomic Molecules • Heck No Halogens • Named with the element name

37. Common Names for 3 Molecules Molecular name and formula: common name • Dihydrogen monoxide = • Carbon tetrahydride = • Nitrogen trihydride =

38. Methane: CH₄

39. Ammonia: NH₃

40. Water: H₂0

41. Common elements found in the Earth's rocks.

42. Important Minerals found in Rocks