Name:_____________________
EST 4: Properties of solutions
Solutions are important to chemistry because it is the best way to mix chemicals so that
they are in contact with each other. A solution is a homogeneous mixture made up of a solute
and a solvent. A solute exists as single atoms (such as metal atoms in an alloy), ions (such
as Na+ and Cl- ions in a NaCl solution), or molecules such as sugar molecules (C6H12O6)
dispersed throughout the solvent. An aqueous solution is a solution where water is the solvent.
Part I: Follow the procedures to prepare solutions, A, B, and C:
Procedure Solution A:
1. Measure 40ml of distilled water in a 50mL graduated cylinder.
2. Weigh out 6g of Dextrose (C6H12O6).
3. Add the dextrose to the 40mL of water.
4. Stir the solution with a glass rod to dissolve the Dextrose.
5. Read the volume of the solution of dextrose on the graduated cylinder.
6. Discard the solution in the sink.
Mass of solute (g) Volume of water (L) Volume of solution (L)
Procedure Solution B:
1. Weigh out 6 g Dextrose (C6H12O6).
2. Place the dextrose in a 50mL graduated cylinder.
3. Add about 25ml of distilled water to the dextrose.
4. Stir the solution with a glass rod to dissolve the Dextrose.
5. add distilled water to the 40mL mark.
6. Stir one more time to homogenize the solution.
7. Pour the solution in a small beaker labeled B, set aside.
Mass of solute (g) Volume of water (L) Volume of solution (L)
Procedure Solution C: DILUTION
1. Locate the 0.02g/L NaCl solution.
2. Use a pipette to add exactly 2mL of the 0.02g/L NaCl solution in a 10mL
graduated cylinder.
3. Add distilled water until you reached the 10mL mark.
4. Pour the solution in a small beaker labeled C, set aside.
Volume of NaCl solution(mL) Volume of water (L) Volume of solution (L)
Concentration: 0.02g/L
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Part II: Electrolytes and pH level of solutions
Procedure: Electrolytes and pH of the solutions
1. Pour some of the solution to be tested (conductivity and pH) in a clean plastic cup.
2. Rinse the electrodes of the conductivity tester with distilled water.
3. Immerse the electrodes of the conductivity tester into the solution to be tested.
4. Observe the brightness of the light (enter your observation in the table)
5. Rinse the electrodes of the conductivity tester with distilled water.
6. Use the universal pH paper strips to determine the pH of the solution to be tested
7. Immerse the tip (1 cm) of the pH paper
8. Enter your observation in the table. (color of the pH paper and pH)
9. Pour the solution back in its original container (beaker B or C or test tubes)
10.Rinse the cup with distilled water and proceed with the next solution (step 1 to 9)
INFO: Test the solutions in the order presented in the table
Observations:
1)Distilled 2)SolutionB 3)SolutionC 4)Nitric
5)Ferrous
6)Sodium
water
C6H12O6(aq)
NaCl (aq)
acid
chloride
Hydroxide
(H2O)
HNO3(aq)
FeCl2(aq)
NaOH (aq)
Conductivity
tester.
(brightness)
Color of the
strip
pH
Part III: Chemical reactions: Formation of precipitate
PART A: A solution of Sodium Hydroxide (NaOH(aq)) is added to a solution of Ferrous chloride
(FeCl2(aq))
Procedure precipitate:
1. Use the plastic pipette to add ≈30 drops Sodium Hydroxide solution (NaOH(aq)) to the
test tube labeled (FeCl3)
(5mL)
2. Observe the reaction in the test tube.
3. Wait 2-3 minutes
4. Set a funnel and filter above a clean test tube
5. Filter the solution.
Observations:
Precipitate color
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PART B:
It is sometime necessary, for environmental concerns, to determine the presence of
Phosphate in lakes and rivers. This precipitation reaction offers a qualitative method to
determine the presence of Phosphate in a solution. If a yellow precipitate is formed, the
solution tested contains some phosphate.
Procedure:
1. Add a pinch of Ammonium molybdate to the test tube marked (x).
2. Gently warm the content of the test tube in a hot water bath on a hot plate until the
Ammonium molybdate is completely dissolved.
3. Use the plastic pipette to add 6 drops of Nitric acid to the test tube.
4. Observe the reaction in the test tube. (record your observation)
5. Discard the content of the test tube in the sink.
Observations:
Precipitate color
EST Properties of Solutions Lab Questions


There will be no formal lab report for this lab. The questions below are the assessment.
Label every section and question clearly, show all work and box the answer)
PART I
SOLUTION A:
1. Calculate the concentration of solution A in g/L
2. Calculate the Molarity (M) of solution A in mol/L
mass(g)
volume(cm3 )
3. Calculate the density of solution A.
Density =
4. Calculate the density of dextrose
1cm3=1 mL
SOLUTION B:
1. Calculate the concentration of solution B in g/L
2. Calculate the Molarity (M) of solution B in mol/L
3. Why do solutions A and B have different concentrations?
4. Write down the steps to prepare 125mL of a 0.028 mol/L dextrose solution. Show
your calculations.
SOLUTION C:
1. Calculate the concentration of solution C in mol/L
2. Calculate the concentration of solution C in g/L
3. Calculate the concentration of solution C in ppm
4. Write down the steps to follow to prepare 0.5L of a 0.5ppm NaCl solution using the
0.02g/L solution as the stock solution.
5. What is the concentration of that solution in mol/L
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Part II:
ELECTROLYTES:
1. Write down the electrolytic dissociation chemical equations for these compounds
a) NaCl
b) HNO3
c) FeCl2
d) NaOH
e) C6H12O6
2. Which of these compounds form ions in an aqueous solution? Explain your answer.
3. Which one of the compounds does not form ions in solution?
4. Rank the tested solutions from most to least conductive.
pH OF THE SOLUTIONS:
1. Rank the solutions tested from most to least acidic.
2. How much more acidic is the solution of Dextrose compared to the solution of
Sodium hydroxide? (text p 60-61)
Part III: Formation of Precipitates
1. How can you tell that a chemical reaction occurred when you added the Sodium
hydroxide solution to the Ferrous chloride solution?
2. What is the name of the liquid that goes through the filter? What is the name of the
product that stays in the filter?
3. What can be said about the precipitate that was formed? Is it soluble or insoluble in
water?
4. In your opinion, would the precipitate be a good electrolyte? Why?
5. Was there any phosphate in the tested solution? Explain your answer.
6. Which industry could potentially release Phosphate in the environment? What effect
could it have on the environment?
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