2. Chapter 41 Aqueous Reactions and Solution Stoichiometry Chapter 4

3. 2 Chapter 4 Topics Properties of aqueous solutions Types of reactions –Precipitation –Metathesis –Acid-Base –Oxidation – Reduction (skip this section=pages 137- 144) Concentrations of solutions –Molarity

4. Chapter 43 Solution A homogeneous mixture of two or more substances The compound that is present in the greater quantity is called the solvent The other compound is called the solute In an aqueous solution, the solvent is water.

5. Chapter 44 Salt water Sodium chloride dissolved in water. NaCl is the solute Water is the solvent

6. Chapter 45 Ionic Compounds in Water Ions dissociate in water. In solution, each ion is surrounded by water molecules. Transport of ions through solution causes flow of current. Properties of Solutes in Aqueous Solution

7. Chapter 46 Ionic Compounds in Water Properties of Solutes in Aqueous Solution (a)An ionic compound dissolving in water (b)A molecular compound dissolving in water

8. Chapter 47 Molecular Compounds in Water Molecular compounds in water (e.g., CH 3 OH): no ions are formed. If there are no ions in solution, there is nothing to transport electric charge. Properties of Solutes in Aqueous Solution

9. Chapter 48 Strong and Weak Electrolytes Strong electrolytes: completely dissociate in solution. For example: Weak electrolytes: produce a small concentration of ions when they dissolve. These ions exist in equilibrium with the unionized substance. For example: Properties of Solutes in Aqueous Solution

10. Chapter 49 Used to highlight reaction between ions. Molecular equation: all species listed in their molecular forms: HCl(aq) + NaOH(aq)  H 2 O(l) + NaCl(aq) Ionic Equations

11. Chapter 410 Used to highlight reaction between ions. Molecular equation: all species listed in their molecular forms: HCl(aq) + NaOH(aq)  H 2 O(l) + NaCl(aq) Complete ionic equation : lists all ions: H + (aq) + Cl - (aq) + Na + (aq) + OH - (aq)  H 2 O(l) + Na + (aq) + Cl - (aq) Note that only strong electrolytes are written in ionic form. Ionic Equations

12. Chapter 411 Used to highlight reaction between ions. Molecular equation: all species listed in their molecular forms: HCl(aq) + NaOH(aq)  H 2 O(l) + NaCl(aq) Complete ionic equation: lists all ions: H + (aq) + Cl - (aq) + Na + (aq) + OH - (aq)  H 2 O(l) + Na + (aq) + Cl - (aq) Net ionic equation : lists only unique ions: H + (aq) + OH - (aq)  H 2 O(l) Note that only strong electrolytes are written in ionic form. Ionic Equations

13. Chapter 412 Metathesis reactions involve swapping ions in solution: AX + BY  AY + BX. Metathesis reactions will lead to a change in solution if one of three things occurs: an insoluble solid is formed (precipitate), weak or nonelectrolytes are formed, or an insoluble gas is formed. Metathesis Reactions

14. Chapter 413 Metathesis Reactions BaCl 2 + K 2 SO 4 BaSO 4 (s) + KCl BaCl 2 + K 2 SO 4 BaSO 4 (s) + 2KCl

15. Chapter 414 Solubility Guidelines for Ionic Compounds Metathesis Reactions Table 4.1 Page 127 Group I and NH 4 + soluble

16. Chapter 415 What’s soluble? 2KI + Pb(NO 3 ) 2 2 KNO 3 + PbI 2

17. Chapter 416 Solubility Guidelines for Ionic Compounds Metathesis Reactions 2KI + Pb(NO 3 ) 2 2 KNO 3 + PbI 2(s)

18. Chapter 417 Acids Dissociation = pre-formed ions in solid move apart in solution. Ionization = neutral substance forms ions in solution. Acid = substances that ionizes to form H + in solution (e.g. HCl, HNO 3, CH 3 CO 2 H, lemon, lime, vitamin C). Bases = substances that react with the H + ions formed by acids (e.g. NH 3, Drano™, Milk of Magnesia™). Acids, Bases, and Salts

19. Chapter 418 Strong and Weak Acids and Bases Strong acids and bases are strong electrolytes. They are completely ionized in solution. Weak acids and bases are weak electrolytes. They are partially ionized in solution. Acids, Bases, and Salts Ammonia is a weak base; ammonia is a weak electrolyte

20. Chapter 419 Memorize these 7 Strong Acids (pg 132) HCl HBr HI HClO 3 (chloric acid) HClO 4 (perchloric acid) HNO 3 (nitric acid) H 2 SO 4 (sulfuric acid)

21. Chapter 420 And the strong bases (pg 132) Group I hydroxides Heavy Group II hydroxides ( Ca & down)

22. Chapter 421 Strong and Weak Acids and Bases Water soluble and ionic = strong electrolyte (probably). Water soluble and is a strong acid (or base) = strong electrolyte. Water soluble and is a weak acid or base = weak electrolyte. Otherwise, the compound is probably a nonelectrolyte. Acids, Bases, and Salts

23. Chapter 422 Strong and Weak Acids and Bases Acids, Bases, and Salts

24. Chapter 423 Neutralization Reactions and Salts Neutralization occurs when a solution of an acid and a base are mixed: HCl(aq) + NaOH(aq)  H 2 O(l) + NaCl(aq) Notice we form a salt (NaCl) and water. Salt = ionic compound whose cation comes from a base and anion from an acid. Neutralization between acid and metal hydroxide produces water and a salt. Acids, Bases, and Salts

25. Chapter 424 Molarity Solution = solute dissolved in solvent. Solute: present in smallest amount. Water as solvent = aqueous solutions. Change concentration by using different amounts of solute and solvent. Molarity: Moles of solute per liter of solution. If we know: molarity and liters of solution, we can calculate moles (and mass) of solute. Solution Composition

26. Chapter 425 Molarity Molarity: Moles of solute per liter of solution. Solution Composition

27. Chapter 426 Molarity: Moles of solute per liter of solution. What is the Molarity of 20 grams of NaCl dissolved in water to a volume of 1L? 20 grams x (1mole NaCl / 58 grams) = 0.34 moles per liter. Therefore 0.34M NaCl Solution Composition

28. Chapter 427 Dilution We recognize that the number of moles are the same in dilute and concentrated solutions. So: M dilute V dilute = moles = M concentrated V concentrated Solution Composition

29. Chapter 428 How many milliliters of 3.0M H 2 SO 4 are required to make 450 mL of 0.10M H 2 SO 4 ? M dilute V dilute = moles = M concentrated V concentrated V conc = M dil x V dil / M conc V conc = (0.10M)(450mL) / 3.0M V conc = 15 mL Solution Composition