Experiment 6, Single Displacement Reactions Chemistry 201, Wright College, Department of Physical Science and Engineering

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1 Name Date Experiment 6, Single Displacement Reactions Chemistry 201, Wright College, Department of Physical Science and Engineering In this experiment you will be doing 2 types of single displacement reactions, Part A: metal (s) + HCl (aq) Part B: metal (s) + metal cation (aq) Both types of reactions are oxidation-reduction (redox) reactions. Oxidation is the loss of electrons or an increase in oxidation number. Reduction is the gain of electrons or a decrease in oxidation number. In part A, evidence of a reaction will be an observation of bubbling or fizzing (production of H 2 gas). In Part B, evidence of a reaction will be an observation of a color change, either in the solution or on the metal. All salts that are products are soluble ionic compounds. PRELAB ASSIGNMENT, Part A: metal (s) + HCl (aq) 1. A student combined Ba (s) and HCl (aq). The student observed bubbling, thus a reaction occurred. What are the products of this reaction? Write the balanced molecular equation for this reaction showing coefficients and phase labels. Write the complete ionic equation for this reaction. Write the net ionic equation for this reaction. Assign oxidation numbers to the reactants and products in the net ionic equation. 1

2 Which reactant, Ba (s) or HCl (aq), got oxidized? Which reactant, Ba (s) or HCl (aq), got reduced? Which reactant, Ba (s) or HCl (aq), is the oxidizing agent? Which reactant, Ba (s) or HCl (aq), is the reducing agent? PROCEDURE, Part A: metal (s) + HCl (aq) 1. Obtain a well plate that will be used as a vessel for the six reactions. Place a small amount of metal, as indicated by the photo below, in the appropriate well. 2. To each well containing a sample of metal, add no more than 8 drops of 6 M HCl solution. If you see a reaction (bubbling/fizzing) with just 1 drop of acid, there is no need to add any more acid. 2

3 3. Allow 10 to 15 minutes for a reaction to occur. Complete the table below with your observation and data. 4. Waste disposal: Use your spatula to scoop any unreacted metal in the beaker labeled, Solid Waste and use your pipet to transfer any solution to the container labeled, Liquid Waste. Wash your well plate with soap and water in the sink. You will need it for part B. Metal (s) Reaction? (yes/no) Observations(extremely reactive, moderately reactive, slow to react, non-reactive) Ca Cu Mg Fe Sn Zn Rank the metals in order of reactivity with HCl (aq). If there is a tie, change the symbol to =. > > > > > most reactive non-reactive For the reaction, Ca (s) and HCl (aq), write the molecular, complete ionic and net ionic equations. 3

4 For the reaction, Fe (s) and HCl (aq), write the molecular, complete ionic and net ionic equations. Note: most likely charge on the iron cation is +2. For the reaction, Mg (s) and HCl (aq), write the molecular, complete ionic and net ionic equations. 4

5 PRELAB ASSIGNMENT, Part B: metal (s) + metal cation (aq) 1. A student combined Mn (s) and Cu(NO3)2 (aq). The student observed a change in color of the metal and the solution, thus a reaction occurred. What are the products of this reaction? Note: most likely charge on the manganese cation is +2. Write the balanced molecular equation for this reaction showing coefficients and phase labels. PROCEDURE, Part B: metal (s) + metal cation (aq) 1. Obtain a second well plate that will be used as a vessel for the reactions in part B. Place a small amount of metal, as indicated by the photo below, in the appropriate well. 2. Add about 8 drops of the indicated solution, as indicated by the photo below, in the appropriate well. Add a few drops of blue Cu(NO3)2 (aq) to an empty well to serve as a blank. Do the same with yellow Fe(NO3)3 (aq). 3. If you see a reaction (color change of metal or solution), write RXN in the table below. Allow 10 to 15 minutes for a reaction to occur. If there is no reaction, write NR in the table below. 5

6 4. Waste disposal: Use your spatula to scoop any unreacted metal in the beaker labeled, Solid Waste and use your pipet to transfer any solution to the container labeled, Liquid Waste. Wash your well plates with soap and water in the sink and return to the designated bin. Ca(NO3)2 (aq) Cu(NO3)2 (aq) Fe(NO3)3 (aq) Mg(NO3)2 (aq) Zn(NO3)2 (aq) Cu (s) XXXXXXX Fe (s) XXXXXXX Mg (s) XXXXXXX Zn (s) XXXXXXX Rank the metals in order of reactivity. If there is a tie, change the symbol to =. > > > most reactive non-reactive For the reaction, Zn (s) and Cu(NO3)2 (aq), write the molecular, complete ionic and net ionic equations. Note: most likely charge on the zinc cation is +2. 6

7 For the reaction, Mg (s) and Fe(NO3)3 (aq), write the molecular, complete ionic and net ionic equations. 7

8 QUESTIONS (Show your work) 1. Write the balanced molecular, complete ionic and net ionic equations, including phase labels, for the reaction of Na (s) and HCl (aq). Assign oxidation numbers to the reactants in the net ionic equation, and then label each reactant as oxidizing agent or reducing agent. 2. Write the balanced molecular, complete ionic and net ionic equations, including phase labels, for the reaction of Ca (s) and Al(NO3)3 (aq). Assign oxidation numbers to the reactants in the net ionic equation, and then label each reactant as oxidizing agent or reducing agent. Updated MV 8