4.7 Experiment: Polar or Nonpolar Substances © 2004 Lois Fruen
This site accompanies the textbook The Real World of Chemistry 7th ed by Lois Fruen Kendall/Hunt Publishing ISBN 0-7575-1001-9

Purpose: To determine the general rule for solubility of polar and nonpolar substances.

Disposal: Non-polar solvents must not be put down the drain. Dispose of all nonpolar solvents in the bottle marked ‘nonpolar solvents’ in the fume hood.

Procedure:

1. Add a small amount of solute on the tip of a spatula to a small, dry test tube that is half full of solvent, and then stir with a stirring rod. Test each solute in each solvent. If any of the solute dissolves, consider it to be soluble.

2. Test each solvent in the other solvents. Record whether the solvents dissolve in each other.

Solutes	Solvents
naphthalene (nonpolar)	water
cobalt (II) chloride	carbon tetrachloride
cupric sulfate
aluminum potassium sulfate
ammonium nitrate
dichlorobenzene (nonpolar)

3.  There are two types of packing materials available: peanuts and styrofoam. Test them in each solvent.

4.  Write the formula and determine polarity of each solute and solvent except for naphthalene and dichlorobenzene.

4.  Write the formula and determine polarity of each solute and solvent except for naphthalene and dichlorobenzene, which are nonpolar.

5.  Using your data, determine a general rule for solubility of polar and nonpolar solutes and solvents.

6.  Using the general rule for solubility, determine the polarity of the peanuts and of the styrofoam, and then explain in your discussion the environmental impacts of using each of these materials for packing.