Lab Activity 9: Differences Between Ionic and Covalent Compounds

 

Purpose:

The purpose of this lab is to devise a set of procedures in order to identify known samples of substances as Ionic or Covalent.  In order to do this, you will be testing the substance in order to determine some simple properties (solubility, melting time, & conductivity).  After you have gathered this information, and organized it in a table (see below) you will then use your knowledge of ionic and covalent substances to determine which of these belong in.  In your abstract, make sure to include any and all pertinent information on covalent and ionic bonding.

***************You must come up with your own procedures******************

 

Materials:

-Centigram Balance     -6 test tube stoppers   -Glazed Paper

-Graduated Cylinder     -Beaker (250 ml)        -Bunsen Burner

-Test-Tube Rack         -Safety Goggles         -Lab Apron

-6 Crucibles                -Ring Stand               -Metal Ring

-Wire Gauze               -Stirring Rod              

Reagents:

-Benzoic Acid, C6H5COOH             -Magnesium Chloride, MgCl2

-Potassium Iodide, KI                  -Sodium Nitrate, NaNO3

-Sucrose, C12H22O11                   -Methanol

-Paradichlorobenzene, C6H4Cl2  

 

SUBSTANCE

SOLUBILITY IN

MELTING TIME

ELECTRICAL CONDUCTIVITY OF SOLUTION

Room Temp Water

Hot Water

Methanol

1.Benzoic Acid

 

 

 

 

 

2.Magnesium Chloride

 

 

 

 

 

3.Paradichlorobenzene

 

 

 

 

 

4.Potassium Iodide

 

 

 

 

 

5.Sodium Nitrate

 

 

 

 

 

6.Sucrose

 

 

 

 

 

Responses:

insol = insoluble

 

short

conductor

sol. = soluble

 

long

nonconductor

 

Additional Notes:

-You must measure out and use 2 grams of each substance.

-Divide the 2 grams into 2 piles (~1 gram each pile.)

-Put about 10 mls of room temp water into the test tubes to do the solubility test.

-Use the beaker of water and Bunsen burner to heat up a water bath. 

-Use this water bath to then heat-up your test tube with solution to determine the solubility in hot water. (You can place all test tubes/solutions in the water bath to avoid reheating.)

-Use the crucible and Bunsen burner to perform the melting time test.  You should still have about one gram of each substance to perform this test.

-I will perform/demonstrate the conductivity of each substance using a “Conductivity Tester."