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Solubility and Properties of Solutions Lab
Purpose: To test the solubility of various solutes and to observe properties of a true solution.
Chemicals:
Epsom salts
Sugar
Table salt
Milk
tap water
vinegar
vegetable oil
rubbing alcohol
Equipment:
25 mL beaker
100 mL beaker
flask
flashlight
Stirring rod
Large test-tube
graduated cylinder
(measuring spoons)
Procedure:
Part I
1) Add 150 mL of water to a 250 mL beaker. Add 2 mL of sugar to the water and swirl the contents of the beaker to
dissolve the sugar. Allow the solution to stand for 5 minutes. Using a flashlight, shine a bright narrow beam of
light from one side of the glass through the solution to the other side of the glass. Move the beam around,
closer and farther away from the glass, trying to see if you can see the path of the beam of light going through
the solution. Record your observations in step 1 of Data Table #1. Save this solution for the following step.
2) Add 1 mL (¼ tsp.) of milk to the above solution in the beaker, swirl the contents and repeat the procedure with
the beam of light described above. Record your observations in Data Table # 1, beside “Step 2”
Part II
3) Add 25 mL of tap water to a 100 mL beaker and add 1 mL (¼ tsp.) of table salt. Swirl the contents of the beaker
to dissolve all the salt. Add a few crystals of salt and swirl the contents of the beaker again. Save this solution for
the next step. Record your observations beside “Step 3”.
4) Add 15 mL (1 Tbsp.) of salt to the solution in step 3. Swirl the contents of the beaker to try to dissolve all of the
salt. Record your observations in Data Table #1, beside “Step 4”.
5) Pour off the liquid in the beaker into an empty 100 mL beaker, leaving any undissolved salt crystals behind. Add
1 mL (¼ tsp.) of salt to the liquid you poured off. Swirl the contents of the beaker to try to dissolve the added
salt. Record your observations.
6) Add 25 mL of water to the beaker in step 5 containing the newly added 1 mL of salt. Swirl the contents of the
beaker to try to dissolve the salt. Record your observations.
Part III
7) Allow the water from a hot water tap to run for awhile to get the water as hot as possible. Place 25 mL of this
hot water into a large test-tube. Add 10 mL (2 tsp.) of Epsom salts and swirl the contents of the test-tube to
dissolve the Epsom salts. Allow the cold water from a cold water tap to run to get the water as cold as possible.
Fill a flask with cold water. Place the hot water /Epsom salts test-tube in the flask, making sure that the cold
water surpasses the level of the hot water solution in the test-tube, without any cold water actually entering
the test-tube. Allow to stand for 5 minutes and observe. Add 1 lone Epsom salt crystal. Record your observations
Part IV
8) Complete Data table # 2. Add 1 mL (¼ tsp.) of the given solute to 5 mL (1 tsp.) of the given solvent. Stir to mix
completely. Omit the combinations indicated by “--”. Record which solutes are soluble in each solvent or
insoluble (immiscible).
Clean Up: Empty the liquids into the sink and rinse with plenty of water. Wash and return all equipment.
Results and Interpretation: Complete the following data tables.
Step
Observations
Data Table #1 (for parts I, II and III)
Is this a solution? If so,
which type of solution
(unsat, sat, supersat)
Explanation/Reasons to Support your
interpretation
1
2
3
Before adding extra salt
4
5
Before adding extra salt
6
7
Solute / Solvent
Water
Vegetable oil
Rubbing alcohol
Table salt
vinegar
Data Table #2 (for part IV)
Indicate if a solution formed : Y (yes) or X (no)
Water
Vegetable oil
-----
Rubbing alcohol
---
Analysis and Concluding Questions:
1. The “Tyndall Effect” is the scattering of a beam of light as it passes through matter. A true solution does not
show the Tyndall Effect, while a mixture which is not a true solution will exhibit the Tyndall Effect. Using this
test, explain your observations for steps 1 and 2. Be sure to include mention of whether each of these is a true
solution.
2. In general, which type of solutes were soluble in which type of solvents? (Don’t just repeat observations from
above table). Explain.
3. Epsom salts is a compound with similar bonding to that of table salt. In which of the solvent(s) used in this
experiment would you predict the Epsom salts to be soluble? Why?