1. Reactions in Aqueous Solution Chapter 4 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

2. 4.1 A _______________ is a homogenous mixture of 2 or more substances The __________ is(are) the substance(s) present in the smaller amount(s) The _____________ is the substance present in the larger amount SolutionSolventSolute(s) Soft drink (l) Air (g) Soft Solder (s) H2OH2O N2N2 Pb Sugar, CO 2 O 2, Ar, CH 4 Sn

3. An ___________ is a substance that, when dissolved in water, results in a solution that can conduct electricity. A _____________ is a substance that, when dissolved, results in a solution that does not conduct electricity. ______________ 4.1

4. Strong Electrolyte – _______% dissociation NaCl (s) Na + (aq) + Cl - (aq) H2OH2O Weak Electrolyte – _________________________ CH 3 COOH CH 3 COO - (aq) + H + (aq) Conduct electricity in solution? __________ (+) and __________(-) 4.1

5. _________ is the process in which an ion is surrounded by water molecules arranged in a specific manner.   H2OH2O

6. _______________ does not conduct electricity No cations (+) and anions (-) in solution 4.1 C 6 H 12 O 6 (s) C 6 H 12 O 6 (aq) H2OH2O ______________ HClCH 3 COOH(NH 2 ) 2 CO HNO 3 HFCH 3 OH HClO 4 HNO 2 C 2 H 5 OH NaOHH2OH2OC 12 H 22 O 11 Ionic Compounds

7. Precipitation Reactions ____________ –insoluble solid that separates from solution ________________________ Pb 2+ + 2NO 3 - + 2Na + + 2I - PbI 2 (s) + 2Na + + 2NO 3 - Na + and NO 3 - are ____________ ions PbI 2 Pb(NO 3 ) 2 (aq) + 2NaI (aq) PbI 2 (s) + 2NaNO 3 (aq) precipitate Pb 2+ + 2I - PbI 2 (s) 4.2

8. Writing Net Ionic Equations 1.Write the balanced molecular equation. 2.Write the ionic equation showing the strong electrolytes 3.Determine precipitate from solubility rules 4.Cancel the spectator ions on both sides of the ionic equation AgNO 3 (aq) + NaCl (aq) AgCl (s) + NaNO 3 (aq) 4.2 Write the net ionic equation for the reaction of silver nitrate with sodium chloride.

9. Solubility Rules for Common Ionic Compounds In water at 25 0 C Soluble CompoundsExceptions Compounds containing alkali metal ions and NH 4 + NO 3 -, HCO 3 -, ClO 3 - Cl -, Br -, I - Halides of Ag +, Hg 2 2+, Pb 2+ SO 4 2- Sulfates of Ag +, Ca 2+, Sr 2+, Ba 2+, Hg 2+, Pb 2+ Insoluble CompoundsExceptions CO 3 2-, PO 4 3-, CrO 4 2-, S 2- Compounds containing alkali metal ions and NH 4 + OH - Compounds containing alkali metal ions and Ba 2+ 4.2 Memorize!

10. Acids Have a sour taste. Vinegar owes its taste to acetic acid. Citrus fruits contain citric acid. React with certain metals to produce hydrogen gas. React with carbonates and bicarbonates to produce carbon dioxide gas Have a bitter taste. Feel slippery. Many soaps contain bases. Bases 4.3

11. _________ acid is a substance that produces H + (H 3 O + ) in water _________ base is a substance that produces OH - in water 4.3

12. A __________ acid is a proton donor A __________ base is a proton acceptor acidbaseacidbase 4.3 A __________ acid must contain at least one ionizable proton!

13. ______________ acids HCl H + + Cl - HNO 3 H + + NO 3 - CH 3 COOH H + + CH 3 COO - Strong electrolyte, strong acid Weak electrolyte, weak acid ______________ acids H 2 SO 4 H + + HSO 4 - HSO 4 - H + + SO 4 2- Strong electrolyte, strong acid Weak electrolyte, weak acid ______________ acids H 3 PO 4 H + + H 2 PO 4 - H 2 PO 4 - H + + HPO 4 2- HPO 4 2- H + + PO 4 3- Weak electrolyte, weak acid 4.3

14. ___________________ Reaction acid + base _________ + ________ + ________ All _________ are strong electrolytes. HCl (aq) + NaOH (aq) NaCl (aq) + H 2 O H + + Cl - + Na + + OH - Na + + Cl - + H 2 O H + + OH - H 2 O 4.3

15. Oxidation-Reduction Reactions (electron transfer reactions) 2Mg (s) + O 2 (g) 2MgO (s) 2Mg 2Mg 2+ + 4e - O 2 + 4e - 2O 2- ________ half-reaction (lose e - ) ________ half-reaction (gain e - ) 2Mg + O 2 + 4e - 2Mg 2+ + 2O 2- + 4e - 2Mg + O 2 2MgO 4.4

16. Zn (s) + CuSO 4 (aq) ZnSO 4 (aq) + Cu (s) Zn is ________Zn Zn 2+ + 2e - Cu 2+ is _______Cu 2+ + 2e - Cu Zn is the ________ agent Cu 2+ is the _______ agent 4.4

17. Copper wire reacts with silver nitrate to form silver metal. What is the oxidizing agent in the reaction? Cu (s) + 2AgNO 3 (aq) Cu(NO 3 ) 2 (aq) + Ag (s) Cu Cu 2+ + 2e - Ag + + 1e - AgAg + is ________Ag + is the _____________

18. Oxidation number The charge the atom would have in a molecule (or an ionic compound) if electrons were completely transferred. 1.Free elements (uncombined state) have an oxidation number of zero. Na, Be, K, Pb, H 2, O 2, P 4 = 0 2.In monatomic ions, the oxidation number is equal to the charge on the ion. Li +, Li = +1; Fe 3+, Fe = +3; O 2-, O = -2 3.The oxidation number of oxygen is usually –2. In H 2 O 2 and O 2 2- it is –1. 4.4

19. 4.The oxidation number of hydrogen is +1 except when it is bonded to metals in binary compounds. In these cases, its oxidation number is –1. 6. The sum of the oxidation numbers of all the atoms in a molecule or ion is equal to the charge on the molecule or ion. 5.Group IA metals are +1, IIA metals are +2 and fluorine is always –1. HCO 3 - O =H = 3x-2 + 1 + ? = -1 C = Oxidation numbers of all the atoms in HCO 3 - ? 4.4

20. NaIO 3 Na = O = 3x-2 + 1 + ? = 0 I = IF 7 F = 7x-1 + ? = 0 I = K 2 Cr 2 O 7 O =K = 7x-2 + 2x+1 + 2x? = 0 Cr = Oxidation numbers of all the atoms in the following ? 4.4

21. Types of Oxidation-Reduction Reactions Reaction A + B C S + O 2 SO 2 Reaction 2KClO 3 2KCl + 3O 2 C A + B 00 +4-2 +1+5-2+10 4.4

22. Reaction A + BC AC + B Sr + 2H 2 O Sr(OH) 2 + H 2 TiCl 4 + 2Mg Ti + 2MgCl 2 Cl 2 + 2KBr 2KCl + Br 2 Hydrogen Displacement Metal Displacement Halogen Displacement Types of Oxidation-Reduction Reactions 4.4 0 +1+20 0+40+2 0 0

23. The Activity Series for Metals M + BC AC + B Displacement Reaction M is metal BC is acid or H 2 O B is H 2 Ca + 2H 2 O Ca(OH) 2 + H 2 Pb + 2H 2 O Pb(OH) 2 + H 2 4.4

24. Reaction Cl 2 + 2OH - ClO - + Cl - + H 2 O Element is simultaneously oxidized and reduced. Types of Oxidation-Reduction Reactions Chlorine Chemistry 0 +1 4.4

25. Ca 2+ + CO 3 2- CaCO 3 NH 3 + H + NH 4 + Zn + 2HCl ZnCl 2 + H 2 Ca + F 2 CaF 2 __________________ Classify the following reactions. 4.4

26. Solution Stoichiometry The ________________ of a solution is the amount of solute present in a given quantity of solvent or solution. M = ____________ = moles of solute liters of solution 4.5

27. Solution Stoichiometry What mass of KI is required to make 500 mL of a 2.80 M KI solution? volume KImoles KIgrams KI M KI 500 mL= _____ g KI 166 g KI 1 mol KI x 2.8 mol KI 1 L soln x 1 L 1000 mL x 4.5

29. ________________ is the procedure of preparing a less concentrated solution from a more concentrated solution. Dilution Add Solvent Moles of solute before dilution (i) Moles of solute after dilution (f) = MiViMiVi MfVfMfVf = 4.5

30. How would you prepare 60.0 mL of 0.200 M HNO 3 from a stock solution of 4.00 M HNO 3 ? M i V i = M f V f M i = 4.00 M f = 0.200V f = 0.06 L V i = ? L 4.5 V i = MfVfMfVf MiMi = =

31. Gravimetric Analysis 4.6 1.Dissolve unknown substance in water 2.React unknown with known substance to form a precipitate 3.Filter and dry precipitate 4.Weigh precipitate 5.Use chemical formula and mass of precipitate to determine amount of unknown ion

32. ___________________ In a _____________________ a solution of accurately known concentration is added gradually added to another solution of unknown concentration until the chemical reaction between the two solutions is complete. ________________ – the point at which the reaction is complete _______________ – substance that changes color at (or near) the equivalence point Slowly add base to unknown acid UNTIL The indicator changes color (pink) 4.7

33. What volume of a 1.420 M NaOH solution is required to titrate 25.00 mL of a 4.50 M H 2 SO 4 solution? 4.7 BALANCE THE CHEMICAL EQUATION! volume acidmoles acidmoles basevolume base H 2 SO 4 + NaOH H 2 O + Na 2 SO 4 M acid rx coef. M base

34. What volume of a 1.420 M NaOH solution is Required to titrate 25.00 mL of a 4.50 M H 2 SO 4 solution? 4.7 BALANCE THE CHEMICAL EQUATION! volume acidmoles acidmoles basevolume base H 2 SO 4 + 2NaOH 2H 2 O + Na 2 SO 4 4.50 mol H 2 SO 4 1000 mL soln x 2 mol NaOH 1 mol H 2 SO 4 x 1000 ml soln 1.420 mol NaOH x 25 mL = _____ mL M acid rx coef. M base

35. (4.72 p.120) What volume of a 0.500 M KOH solution is required to titrate 10.0 mL of a 0.20 M H 2 SO 4 solution? 4.7 volume acidmoles acidmoles basevolume base H 2 SO 4 + KOH H 2 O + K 2 SO 4 ___ mol H 2 SO 4 ____ mL soln x __ mol KOH __ mol H 2 SO 4 x ____ ml soln ____ mol KOH x 10.0 mL = ___ mL M acid rx coef. M base

36. (4.72 p.120) What volume of a 0.500 M KOH solution is required to titrate 10.00 mL of a 0.20 M H 2 SO 4 solution? 4.7 volume acidmoles acidmoles basevolume base H 2 SO 4 + 2KOH 2H 2 O + Na 2 SO 4 0.20 mol H 2 SO 4 1000 mL soln x 2 mol KOH 1 mol H 2 SO 4 x 1000 ml soln 0.500 mol KOH x 10.0 mL = _____ mL M acid rx coef. M base