Electron Configurations in Atoms and Ions 


Name(s):
Date:

 

Objectives:

1.                             Compare chemical reactions of cations with a base and an aqueous solution of a salt.

2.                             Predict results using electron configuration

 

1.     Draw the electron configuration of each of the cations in question.

2.     Arrange these cations into 2 catagories and state your reasoning for this arrangement. (There is more than one arrangement possible)


***Safety:*** All regular safety precautions must be taken.  Also, use CAUTION with nitrates. They must not contact any other class of chemicals.  Sodium hydroxide (NaOH) is caustic and corrosive. Wash hands immediately iof contact with skin is suspected. Cobalt compounds may NOT go down the drain - they go in the waste beaker provided by sink in back of room.

 

You MUST wear goggles, gloves, and aprons.

 

Discussion:

When a chemical reaction occurs, vivid color changes often result when there are unfilled "d" orbitals present.  You will be making observations of the reaction of metallic ion solutions with sodium hydroxide and sodium carbonate and relating them to electron configurations of the metallic ions.

 

Materials:  microplates, beakers, medicine droppers; very small samples of each of the following chemicals:

 

Sodium hydroxide (NaOH), sodium carbonate (Na2CO3),

Sodium chloride (NaCl), magnesium sulfate (MgSO4), aluminum chloride (AlCl3), iron (III) nitrate (Fe(NO3)3), calcium chloride (CaCl2), nickel (II) sulfate (NiSO4), copper (II) sulfate (CuSO4), zinc chloride (ZnCl2), cobalt nitrate (Co(NO3)2

 

Procedure:  Create a data table in your notebook.  Set up the wells as follows:

(you will do this two times)

 

***A positive test is one where there is a vivid color change upon reaction.

 

 

   NaCl

 

Mg SO4

 

AlCl3

  

   Fe(NO3)3

 

CaCl2

 

NiSO4

 

   CuSO4

 

ZnCl2

 

Co(NO3)2

 

 

 

1.          Record observations of the chemicals in the wells

    before reacting them.

 

2.          Add 2-3 drops of sodium hydroxide to each chemical in

    the wells.  Record your results.

 

3.          Refill the wells with chemcials again. Repeat steps 1

    and 2, but this time add sodium carbonate to each well,

    NOT sodium hydroxide.

 

 

Be sure to clean up your well plates and return them to the proper place. (sink in back of room)

 

Remove the rubber bulb of the droppers and cleam them out before returning them.

 

 

Questions: 

 

1. Make a list of the similar reactions of the metal cations with the two reaction reagents. 

 

 

2.          How well do your observations match your predictions.

    Explain.

 

Conclusion Statement:

(must be at least 4 sentences and contain scientific words)