Name: _______________________________Period: ____________ Date: _______________
Solubility Lab
Purpose: To investigate the solubility of a substance in water, rubbing alcohol, and cooking oil.
Background Information: Solubility is the ability of a substance to dissolve (become trapped in)
another substance. Solubility is based on polarity (the distribution of charge in a compound).
Polar compounds will dissolve other polar compounds as well as ionic compounds. Nonpolar
compounds will dissolve other nonpolar compounds. Hence, the rule is “like dissolves like.”
A solution is formed when one substance dissolves in another substance.
The substance that “dissolved” is called the solute.
The substance that is “doing the dissolving” is called the solvent.
Materials:
Well plates
Rubbing Alcohol
Flour
Test Tubes
Sugar
Cornstarch
Test Tube Rack
Salt
Toothpicks
Baby Powder
Water
Problem # 1: Which substances will dissolve in water?
(Sugar, salt, baby powder, flour, cornstarch)
Hypothesis: I think _____________________________________will dissolve in water.
Procedure:
1. Using a pipette, fill 5 wells half full with water.
2. Add a few grains of substance in each of the 5 wells. Make sure that you start with the
sugar, salt etc.
3. Mix well. Use a different toothpick for each of the substances.
4. Create a data table in your notebook like the one found at your lab station then record
your observations in the data table.
Problem # 2: Which substances will dissolve in rubbing alcohol?
(Sugar, salt, baby powder, flour, cornstarch)
Hypothesis: I think ______________________________will dissolve in rubbing alcohol.
Procedure:
1. Using a pipette, fill 5 wells half full with rubbing alcohol.
2. Add a few grains of substance in each of the 5 wells. Make sure that you start with
the sugar, salt etc.
3. Mix well. Use a different toothpick for each of the substances.
4. Record observations in data table.
5. Thoroughly rinse and dry off well plate when done with both liquids.
Name: _______________________________Period: ____________ Date: _______________
Analysis (Answer in complete sentences):
1. Which compounds/substances were soluble in water?
2. Which compounds/substances were insoluble in water?
3. Were any compounds/substances only partially soluble? If so, which one(s)?
4. Does the amount of the substance affect the solubility (you may want to test this using
one or two of the substances)? Justify your answer using evidence from testing one or
more substances.
5. Water is called the universal solvent because it has the ability to dissolve so many
different substances. Why do you think some substances won’t dissolve in water?
6. Explain how it would be possible to retrieve the original solute from each of the solvents
(i.e. get the salt back out of the water).
Conclusion:
Write a conclusion paragraph which explains the results. Be sure to include a discussion about
physical properties and changes.
Name: _______________________________Period: ____________ Date: _______________
Table # 1:
Substance:
Substances with Water
Observations:
Soluble
Insoluble Polar
Nonpolar
Substances with Rubbing Alcohol
Observations:
Soluble Insoluble Polar
Nonpolar
Sugar
Salt
Baby Powder
Flour
Cornstarch
Table # 2:
Substance:
Sugar
Salt
Baby Powder
Flour
Cornstarch