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Experiment_608_Six Unknown Solutions_1_1_2

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    303070
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    Student Name 

     

    Laboratory Date: 

    Date Report Submitted: 

    ___________________________ 

     

    Student ID 

     

    Experiment Number and Name 

    Experiment 608:  Six Unknown Solutions 

     

     

    Experiment 608:  Six Unknown Solutions 

     

    Section 1:  Purpose and Summary 

     

    • Determine if a chemical reaction has taken place when two solutions are combined. 

    • Determine the identity of six unknown solutions. 

     

    In this experiment, students are provided with a set of six solutions: Cu(NO3)2, CuSO4, BaCl2, KIO3, Na2C2O4, and NaCl, and the same set of solutions in a set of ‘unidentified’ numbered/lettered bottles. Students will conduct different reactions that involve combination of two known solutions and generate experimental data that will help them identify the set of unknown solutions.   

     

    Section 2:  Safety Precautions and Waste Disposal 

     

    Safety Precautions: 

     

    Use of eye protection is recommended for all experimental procedures.  

     

    Wash your hands after working with metal solutions.  Do not eat in the laboratory. 

     

    Waste Disposal: 

     

    While you are doing the experiment, collect all waste into a beaker.  

     

    When you are finished with the experiment, pour the contents of the waste beaker into the inorganic waste container in the fume hood. 

     

    Section 3: Procedure 

     

    To determine whether a reaction occurs or not, observe any bubble formation (gas evolution) in the solution, a change in color of the solution, or formation of a precipitate. Record your observations at the time of mixing. If there is a precipitate, write ‘ppt’, and indicate the color. Where there is no evidence of reaction, write ‘NR’. See the suggested data tables after each section below. 

     

    Part 1:  Known solutions 

     

    1.  Obtain solutions containing the following compounds: Cu(NO3)2, CuSO4, BaCl2, KIO3, Na2C2O4, and NaCl.  

    1.  Obtain a clear plastic or white ceramic well plate and clean thoroughly with tap water. Rinse well with laboratory water. Shake off excess water to dry the plate. 

    1.  Label the top and left side of your well plate with the compounds according to the data table. 

    1.  In each of the wells, combine 2 to 3 drops of each pair of known solutions listed in the data table. Stir mixture with a toothpick or wooden splint. Record your observations. 

    1.  Dispose of reaction mixtures into a designated waste beaker. 

    1.  Clean your well plate thoroughly, rinse with laboratory water, and dry. 

     

     

     

    NaCl 

    KIO3 

    Cu(NO3)2 

    Na2C2O4 

    BaCl2 

    CuSO4 

     

     

     

     

     

    BaCl2 

     

     

     

     

    X

    Na2C2O4 

     

     

     

    X

    X

    Cu(NO3)2 

     

     

    X

    X

    X

    KIO3 

     

    X

    X

    X

    X

     

    Part 2 Unknown Solutions 

     

    1.  Obtain a set of unknown solutions. Record the number of the set you used. This is very important! With no identification of which set you used, your work cannot be graded. 

     

    Record your Unknown Set # tested here:   __________ 

    1.  Label the top and left side of your well plate with the compounds according to the data table. 

    1.  In each of the wells, combine 2 to 3 drops of each pair of unknown solutions listed in the data table. Stir mixture with a toothpick or wooden splint. Record your observations. 

    1.  Dispose of reaction mixtures into a designated waste beaker. 

    1.  Clean your well plate thoroughly, rinse with laboratory water, and dry. 

     

     

     

    F 

    E 

    D 

    C 

    B 

    A 

     

     

     

     

     

    B 

     

     

     

     

    X

    C 

     

     

     

    X

    X

    D 

     

     

    X

    X

    X

    E 

     

    X

    X

    X

    X

     

    Section 4: Identification of Unknown Solutions 

     

    Based on your data and observations above, determine the identity of each of your unknown solutions. Clearly explain each step of your reasoning. 

     

    Solution 

    Identity 

    Experimental basis of your identification 

    A 

     

     

    B 

     

     

    C 

     

     

    D 

     

     

    E 

     

     

    F 

     

     

     

     

     

    Post-lab Questions: 

     

    Write the net ionic equation for each of the reactions that occurred in this experiment. 

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     

     


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