Constructing a Solubility Curve

How much sugar can be dissolved in tea?
PURPOSE: In this virtual lab, you will not be answering this question, but you will be determining how
much of an ionic solute will dissolve in water. Just as a different amount of sugar will dissolve in iced
tea versus hot tea, temperature can have an effect on the solubility of an ionic compound. In this lab,
you will be measuring the mass of solute it takes to make a saturated solution in 100.0 g of water at
various temperatures and then graphing the data using Excel. This type of graph is known as a
solubility curve. You will then use your solubility curve to answer questions about the solubility of
your solute.
_____________________________________(your assigned solute)
1) Log on to the virtual lab at (You may need to load
JAVA which takes a few moments).
Click on Chemistry Regular
Click on Calendars and Help
Under the Help section, click on “Solubility Lab” in the Water CD section. (You may
need to load JAVA. This will take a few moments).
2) Under the FILE menu for the Irydium Chemistry Lab, click on LOAD HOMEWORK.
3) Double click on the folder SOLUBILITY AND SOLIDS.
You will design your own procedure as to how to collect the data you need. You MUST have at
least FIVE data points across the temperature range of 0 to 100oc.
You may figure out how to use the virtual lab on your own or use the following FAQs to guide
How do I get the materials I need on the workbench to begin my experiment?
Double click on the stock bottles of the materials needed. You can move them around
on the workbench by dragging them with the mouse.
How do I put some of the solute into the water?
Once your materials are on the workbench, drag the bottle of solute to the top of the
100 mL flask of water. If you have done it properly, it should now have its cap off with
a spatula in the bottle. Underneath the workbench is a space to type in the mass of
solute you would like to transfer. Type in the amount, then click POUR. There is only
about 130 g of solute in each jar, so if you need more than that, you will need to get
another jar.
How do I set the temperature?
Under the EDIT menu, click on THERMAL PROPERTIES. You MUST check the box
that says INSULATED FROM SURROUNDINGS. If you notice the temperature
reading on the right side of the screen (under Solution Info) fluctuating, go back and
reset temperature and insulation. I don’t know why, but sometimes you must set this
both before and after you add a sample of solute.
How do I know if the solution is saturated?
In the Solution Info at the right side of your screen, click on the button labeled SOLID
(Make sure you have your clicked your cursor on the solution in the flask). If all of the
solid is dissolved, it will say there is 0 grams. Is this a saturated solution?
If not all of the solid dissolved, it will tell you how many grams of solid are still
present. (You may want to review scientific notation). Can you figure out how much
is dissolved? Is this a saturated solution?
What sort of data should I collect?
Look at the purpose of the experiment again to make this determination. If you have to
do any calculations to the raw data to get the data you need to graph, SHOW YOUR
Should I repeat the experiment?
YES!! Because this is a virtual lab, your data should be reproducible. If not, you
probably made an error.
PROCEDURE: Write in your final procedure here. It may take a while working with the program
to determine exactly what your procedure will be.
DATA: Use as much or as little of this blank data table as you need. Or you may make your own.
GRAPH: (attach to report) Plot temperature on the Y-axis and Mass solute on the X-axis. Use the
Instruction Sheet for Excel graphing to make your graph. This is also available on the chemistry
CALCULATIONS: (You may or may not have calculations depending on the design of your
experiment.) Show any work for calculations.
QUESTIONS: (Remember to answer in complete sentences).
1. How does temperature affect the solubility of your ionic solute?
2. Using your solubility curve, give an example of an unsaturated solution (mass/100.0 g water)
at 35oC.
3. Using your solubility curve, give an example of a saturated solution (mass/100.0 g water) at
4. Using your solubility curve, give an example of a supersaturated solution (mass/100.0 g
water) at 35oC.
5. If you had 150.0 g water, how much of your solute would be needed to make a saturated
solution at 55oC?