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Chapter 4 Chemical Quantities and Aqueous Reactions 73 4.65 Given: 95.4 mL; 0.102 M CuCl₂; 0.175 M Find: volume Na₃PO₄ Conceptual Plan: mL CuCl₂ L CuCl₂ mol CuCl₂ mol Na₃PO₄ L Na₃PO₄ mL 1L 0.102 mol CuCl₂ 2 mol 1L 1000 mL 1000 mL L 3 mol CuCl₂ 0.175 mol Na₃PO₄ L 0.102 mol Solution: 95.4 mL 2 1000 mL 1000 mL L X 3 0.175 = 37.1 mL Check: The units of the answer (mL Na₃PO₄) are correct. The magnitude of the answer is reasonable because the concentration of Na₃PO₄ is greater. 4.67 Given: 25.0 g H₂; 6.0 M Find: volume Conceptual Plan: g H₂ mol H₂ mol L 1 mol H₂ 3 mol 1L 2.016 g H₂ 3 mol 6.0 mol Solution: 25.0 2.016 1 3 3 X 6.0 1L = 2.1 L Check: The units of the answer are correct. The magnitude is reasonable because there are approximately 12 mol H₂ and the mole ratio is 1:1. 4.69 Given: 25.0 mL, 1.20 M 15.0 mL, 0.900 M Ba(NO₃)₂ 2.45 g BaCl₂ Find: limiting reactant, theoretical yield BaCl₂, % yield Conceptual Plan: volume KCI solution X M mol KCI mol BaCl₂ 1 mol BaCl₂ smaller mol amount determines volume solution (L) M = mol 2 mol KCI limiting reactant volume Ba(NO₃)₂ solution X M mol Ba(NO₃)₂ mol BaCl₂ 1 mol BaCl₂ volume solution (L) M = mol 1 mol Ba(NO₃)₂ then mol BaCl₂ g BaCl₂ then determine % yield 208.23 g BaCl₂ actual yield g BaCl₂ 100% mol BaCl₂ theoretical yield g BaCl₂ 1 L solution 1.20 Solution: 25.0 solution X 1 mol BaCl₂ 1000 mL solution L solution 2 mol = 0.0150 mol BaCl₂ 1 L solution 15.0 0.900 1 mol BaCl₂ X = 1000 solution 0.0135 mol 1 BaCl₂ 208.23 g BaCl₂ 0.0135 = 2.811 g BaCl₂ 1 2.45 100% = 87.2% 2.811 Types of Aqueous Solutions and Solubility 4.71 (a) is an ionic compound. An aqueous solution is an electrolyte solution, so it conducts electricity. (b) CH₃OH is a molecular compound that does not dissociate. An aqueous solution is a nonelectrolyte solution, so it does not conduct electricity. (c) Ca(NO₂)₂ is an ionic compound. An aqueous solution is an electrolyte solution, so it conducts electricity. (d) C₆H₁₂O₆ is a molecular compound that does not dissociate. An aqueous solution is a nonelectrolyte solution, so it does not conduct electricity. 4.73 (a) AgNO₃ is soluble. Compounds containing are always soluble with no exceptions. The ions in the solu- tion are (aq) and (aq). (b) Pb(C₂H₃O₂)₂ is soluble. Compounds containing C₂H₃O₂⁻ are always soluble with no exceptions. The ions in the solution are (aq) and Copyright © 2017 Pearson Education, Inc.