1. 1 Types of Chemical Reactions and Solution Stoichiometry Chapter 4

2. 2 Water, the Common Solvent Section 4.1

3. 3 Type of bond? Shape? Polarity? Nature of Water Covalent Polar Bent/Angular

4. 4 Ionic solids that dissolve are soluble. Ionic solids will dissolve in polar solvents but not nonpolar solvents Water molecules break the crystal lattice into separate ions. This is dissociation. Then the water molecules surround the ions. This is hydration. Ionic solids that do not dissolve are insoluble. Ionic Solute-Solvent Interaction

5. 5 p. 411 Ionic Solute-Solvent Interaction

6. 6 Solubility of Compounds notes

7. 7 Solubility of Compounds notes

8. 8 Miscible – Liquids that dissolve freely in one another in any proportion. Immiscible – Liquids that are not soluble in each other. “Likes dissolve likes” Polar solutes dissolve in polar solvents. Nonpolar solutes dissolve in nonpolar solvents. Alcohols are slightly polar. Liquid Solute-Solvent Interaction

9. 9 Miscible and Immiscible

10. 10 p. 412 Immiscible & Miscible

11. 11 The Nature of Aqueous Solutions Section 4.2

12. 12 A homogeneous mixture of two or more substances in a single phase Particles are thoroughly mixed and remains mixed indefinitely Components of a solution –Solvent: does the dissolving; the larger amount –Solute: is being dissolved; the smaller amountSolution

13. 13 p. 406 Electric Conductivity in Solutions

14. 14 Electrolyte – a substance that dissolves in water to give a solution that conducts electric current Nonelectrolytes –a substance that dissolves in water to give a solution that does not conduct electricity –Does not produce ions –Example: sugar and ethanol Electrolytes & Nonelectrolytes

15. 15 Completely ionized when they are dissolved in water Three classes –Soluble Salts –Strong Acids: produce H + ions when dissolved in water HCl (g) + H 2 O (l)  H 3 O + (aq) + Cl - (aq) –Strong Bases: produce OH - ions when dissolved in water NaOH (s)  Na + (aq) + OH - (aq) Strong Electrolytes NaCl (s)  Na 1+ (aq) + Cl 1- (aq)

16. 16  An acid that ionizes completely in aqueous solution.  STRONG ACID LIST  HClhydrochloric acid  HI hydroiodic acid  HBrhydrobromic acid  H 2 SO 4 sulfuric acid  HNO 3 nitric acid  HClO 3 chloric acid  HClO 4 perchloric acid Strong Acids MEMORIZE!

17. 17  Strong Bases – bases that dissociate completely – strong electrolytes  Formed from Group I & II metals combined with hydroxide Strong Bases

18. 18 Substances that exhibit a small degree of ionization in water Two classes –Weak Acids: produce few H + ions when dissolved in water CH 3 COOH (aq) + H 2 O (l)  CH 3 COO - (aq) + H 3 O + (aq) –Weak Bases: produce few OH - ions when dissolved in water NH 3 (aq) + H 2 O (l)  NH 4 + (aq) + OH - (aq) Weak Electrolytes

19. 19 The Composition of Solutions Section 4.3

20. 20 The number of moles of solute in one liter of solution.Molarity M =M =M =M = moles of solute liters of solution M =M =M =M =molL

21. 21 1.Calculate the molarity of a solution prepared by dissolving 11.5 g of solid NaOH in enough water to make 1.50 L of solution. 2.Give the concentrations of each type of ion in the following solutions: a.0.50 M Co(NO 3 ) 2 b.1 M Fe(ClO 4 ) 3 3.Calculate the number of moles of chloride ions in 1.75 L of 1.0 x 10 -3 M ZnCl 2. 4.Typical blood serum is about 0.14 M NaCl. What volume of blood contains 1.0 mg NaCl? Molarity Practice Problems

22. 22 A solution whose concentration is accurately known. –To analyze the alcohol content of a certain wine, a chemist needs 1.00 L of an aqueous 0.200 M K 2 Cr 2 O 7 solution. How much solid potassium dichromate must be weighed out to make this solution? Standard Solution

23. 23 A solution in concentrated form. Dilution: process where water is added to achieve the molarity desired for a particular solution. If the mole ratio is 1:1, then M 1 V 1 =M 2 V 2 can be used –What volume of 16 M sulfuric acid must be used to prepare 1.5 L of a 0.10 M sulfuric acid solution?Dilution

24. 24 Precipitation Reactions Section 4.5

25. 25 Two solutions mix and an insoluble solid forms The solid that forms is called a precipitate. Predicting Reaction Products: –Using the solubility rules, predict what will happen when the following pairs of solutions are mixed. Potassium nitrate and barium chloride Sodium sulfate and lead (II) nitrate Potassium hydroxide and iron (III) nitrate Precipitation Reactions

26. 26 Describing Reactions in Solution Section 4.6

27. 27 NET IONIC EQUATION Write the balanced equation for the reaction between ammonium sulfide and cadmium II nitrate. Be sure to include states of matter What type of reaction is it? What are the products? (NH 4 ) 2 S (aq) + Cd(NO 3 ) 2 (aq)  2 NH 4 NO 3 (aq) + CdS (s)

28. 28 NET IONIC EQUATION Each (aq) is dissociated. The (s) is not dissociated; it is the precipitate. (NH 4 ) 2 S (aq) + Cd(NO 3 ) 2 (aq)  2 NH 4 NO 3 (aq) + CdS (s)

29. 29 NET IONIC EQUATION (NH 4 ) 2 S (aq) + Cd(NO 3 ) 2 (aq)  2 NH 4 NO 3 (aq) + CdS (s) (NH 4 )S ++ Cd 1+ 2- (aq) (NO 3 ) 2+ 1- (aq)  NH 4 NO 3 ++ 1+ 1- (aq) 22 2 2 CdS + (s) Break all (aq) into ions; not the (s) Balance and add states

30. 30 NET IONIC EQUATION (NH 4 ) 2 S (aq) + Cd(NO 3 ) 2 (aq)  2 NH 4 NO 3 (aq) + CdS (s) (NH 4 ) S ++ Cd 1+ 2- (aq) (NO 3 ) 2+1- (aq)  NH 4 NO 3 ++ 1+ 1- (aq) 2 2 2 2 CdS + (s) Identify spectator ions and remove Write what’s left. + 

31. 31 2- NET IONIC EQUATION (NH 4 ) 2 S (aq) + Cd(NO 3 ) 2 (aq)  2 NH 4 NO 3 (aq) + CdS (s) (NH 4 ) S ++ Cd 1+ (aq) (NO 3 ) 2+ 1- (aq)  NH 4 NO 3 ++ 1+ 1- (aq) 2 2 2 2 CdS + (s) This is the net ionic equation. + 

32. 32 Ag(NO 3 ) + NaCl

33. 33 NET IONIC EQUATION Write the balanced equation for the reaction between sodium chloride and silver nitrate. Be sure to include states of matter What type of reaction is it? What are the products? NaCl (aq) + Ag(NO 3 ) (aq)  NaNO 3 (aq) + AgCl (s)

34. 34 NaCl (aq) + AgNO 3 (aq)  NaNO 3 (aq) + AgCl (s) NET IONIC EQUATION NaCl ++ Ag 1+ 1- (aq) NO 3 1+1- (aq)  NaNO 3 ++ 1+ 1- (aq) AgCl + (s) Break all (aq) into ions; not the (s) Balance and add states

35. 35 + NaCl (aq) + AgNO 3 (aq)  NaNO 3 (aq) + AgCl (s) NET IONIC EQUATION Na Cl ++ Ag 1+ 1- (aq) NO 3 1+1- (aq)  NaNO 3 + 1+ 1- (aq) AgCl + (s) Identify spectator ions and remove Write what’s left. + 

36. 36 This is the net ionic equation. + NaCl (aq) + AgNO 3 (aq)  NaNO 3 (aq) + AgCl (s) NET IONIC EQUATION Na Cl ++ Ag 1+ 1- (aq) NO 3 1+ 1- (aq)  NaNO 3 + 1+ 1- (aq) AgCl + (s) + 

37. 37 Stoichiometry of Precipitation Reactions Section 4.7

38. 38 1.When aqueous solutions of sodium sulfate and lead (II) nitrate are mixed, lead (II) sulfate precipitates. Calculate the mass of lead (II) sulfate formed when 1.25 L of 0.0500 M lead (II) nitrate and 2.00 L of 0.0250 M sodium sulfate are mixed. Determining the mass of product formed

39. 39 Acid-Base Reactions Section 4.8

40. 40 Brønsted-Lowry Acid & Base H NH 3(aq) + H 2 O (l)  NH 4 + (aq) + OH - (aq) N H O HH NHH H + OH - H H A molecule or ion that is a proton donor ACID A molecule or ion that is a proton acceptor BASE

41. 41  The reaction of hydronium ions and hydroxide ions to form water molecules. Neutralization Reactions HCl (aq) + NaOH (aq)  NaCl (aq) + HOH (l) ACID + BASE  SALT + WATER H + +Cl - + Na + +OH -  Na + +Cl - + HOH H + (aq) + OH - (aq)  HOH (l)

42. 42  The reaction of hydronium ions and hydroxide ions to form water molecules. Neutralization Reactions HC 2 H 3 O 2 (aq) + KOH (aq)  KC 2 H 3 O 2(aq) + HOH (l) ACID + BASE  SALT + WATER HC 2 H 3 O 2 + K + +OH -  K + + C 2 H 3 O 2 -1 + HOH HC 2 H 3 O 2 (aq) + OH - (aq)  HOH (l) + C 2 H 3 O 2 -1 (aq)

43. 43 1.What volume of a 0.100 M HCl solution is needed to neutralize 25.0 mL of 0.350 M NaOH? 2.In a certain experiment, 28.0 mL of 0.250 M HNO 3 and 53.0 mL of 0.320 M KOH are mixed. Calculate the amount of water formed in the resulting reaction. What is the concentration of H + and OH - ions in excess after the reaction goes to completion. Neutralization Reactions

44. 44 Delivery from a buret of a measured volume of a solution of known concentration (the titrant) into a solution containing the substance to be analyzed (the analyte) Equivalence point: the point in a titration where enough titrant has been added to react exactly with the analyte Endpoint: The point where the indicator actually changes color Acid-Base Titration

45. 45 1.A student weighs out a 1.3009 g sample of KHC 8 H 4 O 4. KHP has one acidic hydrogen. The student dissolves the KHP in distilled water, adds phenolpthalein and titrates the solution with sodium hydroxide to the endpoint. The difference between the final and initial buret readings indicates that 41.20 ML of the sodium hydroxide is required to react exactly with the KHP. Calculate the concentration of sodium hydroxide. Neutralization Titration/Analysis

46. 46 2.An environmental chemist analyzed the effluent from an industrial process known to produce the compounds CCl 4 and HC 7 H 5 O 2, a weak acid with one acidic hydrogen. A sample of the effluent weighing 0.3518 g was shaken with water and the resulting aqueous solution required 10.59 mL of 0.1546 M NaOH for neutralization. Calculate the mass percent of HC 7 H 5 O 2 in the original sample. Neutralization Titration/Analysis