Pre-Lab 7: Solubility and Net Ionic Equations

Name:_____________Section:____________Pre-Lab 7: Solubility and Net Ionic EquationsAnswer the following questions after reading the background information at the beginning ofthe lab. This should be completed before coming to lab.1. Write the balanced equation for dissolving the following solid ionic salts in water:a) NaCl(s)b) Ba(NO 3 ) 2 (s)c) MgF 2 (s)2. Write the total ionic and balanced net ionic equations for the following reactions:a) AgNO 3 (aq) + NaCl(aq) ----> AgCl(s) + NaNO 3 (aq)b) BaCl 2 (aq) + K 2 CrO 4 (aq) ----> KCl(aq) + BaCrO 4 (s)c) KOH(aq) + Fe(NO 3 ) 3 (aq) ----> Fe(OH) 3 (s) + KNO 3 (aq)~ 80 ~

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Lab 7: Solubility and Net Ionic EquationsObjectives: In this experiment you will mix small quantities of aqueous ionic solutions together and insome cases, observe the formation of precipitates.General procedure:1. Mix small quantities of different ionic solutions together.2. Observe the absence or presence of a precipitate and its physical characteristics such ascolor, amount, etc.3. Formulate general solubility rules based on experimental observations.4. Write net ionic equations to describe the precipitation reactions.Safety• Wear safety goggles at all times.• Wear shoes that cover the entire foot.• Never touch, taste or smell chemicals.• Keep your hands away from your face, eyes, nose and mouth.• Always wash your hands before leaving the laboratory..Table of Ionic Salt SolutionsSolution#1Solution#2Solution#3Solution#4Solution#5Solution#6Set I Set IIBa(NO 3) 2Na 2SO 4BaCl 2Al 2(SO 4) 3NaI Sr(NO 3) 2AgNO 3CaCl 2NaNO 3AgNO 3KCl~ 82 ~

Part I. Writing Total Ionic and Net Ionic EquationsStudents will test ionic salt solutions for insoluble products. This is done be systemaicallycombining solutionsEquipment List:‣ Set 1 of the ionic salt solutions‣ 12 well spotting plateProcedure:1.Clean the Twelve well spotting plate.2.Spot a row of 5 spots on the spotting plate.3.Test this row against the other 5 solutionin the first set.4.Look for reactions and make observationsin the charts below.Results5.Choose another solution, and test againstthe remaining 4 solutions.6.Continue until all solutions have beentested against each other.Record observations in the chart below:-Look for precipitates, gas bubbles, etc.-Make notes on any colors seen in the precipitates/changes in solution color.Set # I~ 83 ~

DiscussionFor each of the solutions that showed a reaction, Record the solutions that were reacted andgenerate a total and net ionic equation for each reaction.SolutionsReactedDid AReactionOccur?Write out the Total IonicEquation and Net Ionic Equation~ 84 ~

SolutionsReactedDid AReactionOccur?Write out the Total IonicEquation and Net Ionic EquationAdditional Question #1. Which ion formed the most insoluble products?Additional Question #2. What is the chemical formula for the colored precipitates, and whatare their names?~ 85 ~

Part II. Predicting ReactionsStudents will test ionic salt solutions for insoluble products. This is done by systematicallycombining solutionsEquipment List:‣ Set 3 of the ionic salt solutions‣ 12 well spotting plateProcedure:1. Use the solubility laws to predict ifthe these reactions should occur.2. Record your predictions beforebeginning testing.3. Have the instructor initial the bottomof the page.4. Clean the Twelve well spotting plate.5. Spot a row of 5 spots on the spottingplate.6. Test this row against the other 5solution in the first set.7. Look for reactions and makeobservations in the charts below.8. Choose another solution, and testagainst the remaining 4 solutions.9. Continue until all solutions havebeen tested against each other.PredictionsFor each possible reaction indicate wither a reaction will occur or not, and what the reactionproduct is.Set #2SolutionsReacted1/2Will areactionOccur?Write the Net Ionic Equation for each.1/31/41/52/32/4~ 86 ~

2/53/43/54/5ResultsRecord observations in the chart below:-Look for precipitates, gas bubbles, etc.-Make notes on any colors seen in the precipitates/changes in solution color.Set #2SolutionsReactedDid aReactionOccur?Actual ResultsEvidence?Was thiscorrectlypredicted?1/21/31/41/5~ 87 ~

2/32/42/53/43/54/5~ 88 ~

Solubility and Net Ionic EquationsReport SheetPart I. Writing Total Ionic and Net Ionic EquationsAnswer the following Questions1. Which solids formed non-whiteprecipitates?2. How many reactions had solid products?Name:_________________Partner:________________Section:________________3. Write the net ionic equations for the silvercontaining precipitatesPart II. Predicting ReactionsAnswer the following Questions1. # of incorrect predictions:2. What Ion formed the most solidprecipitates?3. What are the net ionic Equations of theproducts?Additional Questions:1. Which of the following salts are soluble in water and explain why:a) Na 3 PO 4 b) CaCO 32. Explain the following observations using solubility:a) A warm can of soda fizzes up when openedb) One pack of sugar will dissolve in 8 oz.of ice coffee at 35 ◦F , but 3 packets dissolve in ahot cup at 180 ◦F .~ 89 ~