Dissolving of an Ionic Compound 1

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Clicker Question What are the possible products? AgNO 3(aq) + KCl (aq) → ? A) AgCl and KNO 3 B) AgNO 3 and KCl C) AgK and NO 3 Cl D) Any of the above could be the products. 4

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Solubility Rules 6

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Precipitation Reactions  Know how to use the solubility rules (you will be given them on the exam).  Know how to write equations from reactants (ionic reactants).  Understand what solutions “look” like at a very magnified level. 8

Clicker Question When aqueous AgNO 3 and aqueous Na 2 CrO 4 are mixed, what are the formulas of the products? A)Na 2 NO 3 and AgCrO 4 B)NaNO 3 and Ag 2 CrO 4 C)NaNO 3 and AgCrO 4 D)Na 2 NO 3 and Ag 2 CrO 4 9

Clicker Question Given: Na 2 CrO 4(aq) + AgNO 3(aq) → Ag 2 CrO 4 + NaNO 3 Which is the solid? A) NaNO 3 B) Ag 2 CrO 4 Solubility Rules Most nitrate salts are soluble. Most salts of sodium, potassium, and ammonium cations are soluble.  Most chloride salts are soluble. Exceptions: Ag + and Pb 2+.  Most sulfate salts are soluble. Exceptions: Ca 2+, Ba 2+, and Pb 2+.  Most hydroxide salts are only slightly soluble. Soluble ones are: Na +, K +, and Ca 2+.  Most sulfide, carbonate, and phosphate salts are only slightly soluble. 10

Clicker Question Which solution is the most concentrated? 11

Solution Problem #1  You have 1.00 mol of sugar in mL of solution. Calculate the concentration in units of molarity. 12

Solution Problem #2  You have a 2.50 M sugar solution. Calculate the number of moles of sugar in mL of this solution. 13

Solution Problem #3  You have a 10.0 M sugar solution. What volume of this solution do you need to have 2.00 mol of sugar? 14

Clicker Question You add mL of water to mL of a 4.00 M sugar solution. What will happen to the concentration? A)increase B)decrease C)stay the same 15

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Solution Problem #4 You add mL of water to mL of a 4.00 M sugar solution. Calculate the concentration of the new solution in units of molarity. (Assume the volumes are additive.) 17

Solution Problem #5  You dissolve g of NaOH in mL of solution. Determine the concentration of the solution in terms of molarity. 18

Solution Problem #6  We have a M solution of NaOH. You need 75.0 mL of a 0.35 M solution. How do you make such a solution? 19

Solution Problem #7  Answer the following questions for 60.0 mL of 2.00 M calcium chloride solution. a) How many moles of calcium chloride are in solution? How many moles of chloride ions are in this same solution? b) You add 40.0 mL of water to the solution. How many moles of calcium chloride are in the new solution? c) What is the molarity of the new solution? 20