Solubility Lab
Name: ____________________ Date: _________________ Period: __________
This lab is designed to familiarize the students with the concept of solubility and the factors that
affect the rate at which a solute will dissolve in a solvent.
USE THE MODIFIED LAB WRITE UP PROCEDURE ON THE BACK OF THIS LAB
Sugar cubes, granulated sugar, salt, water,1000 ml beaker, 150 ml beakers, thermometer,
Bunsen burner or hot plate, stirring rods, electronic balance, weighing paper, timer, safety
glasses, 100 ml graduated cylinder
1. Fill a 1000 ml beaker with approximately 700 ml of cold tap water.
(record temp = _____ º C).
2. Weigh 3 sugar cubes that are within 5% of each other; record the weight of each:
_______ cube 1 _______ cube 2
_______ cube 3
Divide the highest mass by the lowest. The answer should be no more 1.05. Change
cubes if necessary to achieve this margin.
3. Measure 100 ml room temperature water Place cube 1 in the beaker. DO NOT STIR.
Record the solvation time. ________________ min/sec. ____ final temp. º C. If it does
not completely dissolve after 20 – 30 minutes, visually estimate the amount dissolved in
%. Record any special observations about the liquid.
4. Repeat step 3 with cube 2 but this time stir the beaker until the sugar completely
dissolves. Record the solvation time. __________ min/sec. ____ final temp. º C.
5. Measure 100 ml water, add it to the beaker and warm the water an additional 15 - 20 ºC
before adding cube 3. Record initial water temp ________ º C, stir time _______ min /
sec., and _______ final temp. º C to effect complete solvation.
6. Weigh an amount of granulated sugar equal to cube 1 and completely dissolve it in 100 ml
room temperature water record temp = ______ º C). Record the total stir time and final
temperature ________ min / sec., _______ final temp. º C.
7. Weigh an amount of table salt equal to the average mass of the 3 sugar cubes and
dissolve it with stirring in 100 ml room temperature water record temp = ______ º C).
Record the total stir time and final temperature ______ min / sec. _______ final temp. º C.
8. Repeat step 7 but heat the water an additional 15 - 20 ºC above before adding table salt
and stirring. Record initial water temp ________ º C, stir time _______ min / sec., and
_______ final temp. º C.
Table all results on attached data table
Post Lab Questions
Cite evidence from your data table then answer the following questions:
1.
2.
3.
4.
What was the control in this lab and why is a control important?
What conclusions can be drawn regarding the rate of dissolving with respect to agitation?
How does temperature affect the rate of solvation? Explain in detail.
How does surface are affect the rate of solvation? Explain in detail.
5.
6.
7.
8.
9.
10.
11.
What type of substances were the solutes?
Which solute dissolved the fastest?
Why do you think it dissolved faster than the other substance?
Do you thing the control would eventually dissolve completely? Explain your reasoning.
Why was it important to have the all weights within 5% of each other?
What could some sources of error be in tis lab?
How would you correct for these sources of error?
Make a suggestion for an improvement or something else to try in this lab.
(eating the sugar cubes doesn’t count, nice try!)
LABORATORY WRITE UP INSTRUCTIONS
Number and label each section when writing up the report
Steps 3 – 8 will make this easier to write up. You may discuss these with your lab partners.
1. Names of entire group and the tasks performed by each team member; performed
and due dates.
2. Lab Title and introduction
3. Beginning ideas and questions:
List my ideas, questions, concerns, or opinions about this experiment.
4. Tests and Procedures:
What are the tests and exact procedure that I will do to answer my comments in step 3?
above. Bulleted or dashed step by step instructions without pronouns.
5.
Equipment / materials / apparatus
A tabled, bulleted, or dashed list.
6. Observations:
List all relevant observations (gathered by any of your 5 senses) when you performed the
tests and procedures.
You may use graphs, drawings, charts, tables, etc. to explain or show the
observations
7. Calculations & Graphs
8.
Conclusion and Post lab questions
What did you use to arrive at your claims?
How do you know the evidence is relevant?
Why are you making these claims?
9.
Error analysis and comparisons
How did your results compare with others?
What did you learn?
10. Personal comments: What were your likes and dislikes about the lab?
CUBE 1
MASS G
INITIAL TEMP ° C
FINAL TEMP ° C
DISSOLVE TIME MIN'
SEC"
CUBE 2
CUBE 3
DATA SHEET
SOLUBUILITY
LAB
GRANULATED
SUGAR
GRANULATED
SALT
GRANULATED
SALT