Solubility of NH 4 Cl Lab

Solubility Curve Lab
Purpose: To observe the effect of temperature and solubility and to produce solubility curve for
ammonium chloride.
Procedure:
1. Get materials ready: large test tube, thermometer, ring stand, utility clamp, hot plate, and
a 400 mL beaker for a hot water bath. Start the boiling water immediately.
2. Mass 6.0 grams of ammonium chloride (NH 4 Cl) in the large test tube. Using a pipette,
add 10.0 mL of distilled H 2 O to the test tube.
3. Attach test tube to the ring stand using a utility clamp. Lower the test tube into the hot
water bath.
4. Warm the solution in the water bath until all the solute is dissolved. Do this quickly to
reduce evaporation of the water. Stir gently with the thermometer.
5. After the solute is completely dissolved, take it out of the water bath. As it cools, stir
carefully with the thermometer. Watch closely and record the temperature when the
FIRST crystals are seen. DO NOT REMOVE THERMOMETER DURING THE REST
OF THE EXPERIMENT.
6. Next, using a pipette, add 1.0 mL distilled water to the solution. Repeat Steps 3 and 4.
7. Repeat Steps 3, 4, and 5 until at least four readings are obtained. Record the volume of
water and the temperature of each reading.
Post-Lab:
Calculate grams of NH 4 Cl per 100 grams of water:
1 mL = 1gram water
Use ratio: 6.0 grams NH 4 Cl x grams NH 4 Cl
10.0 g water 100 g water
6.0 grams NH 4 Cl x grams NH 4 Cl
11.0 g water 100 g water
etc.
Graph
1. Open Microsoft Excel.
2. Enter your temperatures in column A and your solubility data (grams of NH 4 Cl per 100 g
of water) in column B.
3. Get a copy of the solubility handout for NH 4 Cl. Enter in all the points from the handout
(again temperature in column C and solubility in column D).
4. Highlight all data entered using the mouse.
5. Click on the Insert Tab. Select the Scatter Option and then select Scatter with Smooth
Lines and Markers.
6. Right click on the graph that appears and click on the select data option.
7. Remove Series 3. Then select Series 2 and click on the edit button.
8. Change the Series name to “Standard Solubility Data”. Change the Series X Values to be
Column C data instead of A data. Change the Series Y Values to be Column D data
instead of C data. Click OK.
9. Click on Series 1 and click on the edit button. Change the Series name to “My Data”.

10. Make sure the graph is still selected. Under the Chart Tools on the far right corner of the
screen, click on layout.
11. Click on Chart Title. Add a title.
12. Click on Axis Title. Add both a x-axis and a y-axis title.
13. Right click on the x-axis. Select Format axis. Under Axis options, change the major unit
to “fixed” and the number to “25.0”. Change the minor unit to “fixed” and the number
“5.0”. Change the minor tick mark type to “outside”. Click close.
14. With the graph still selected, select the windows icon in the upper left corner and then
select the print option. This should print the graph as a full sheet.
Closing Question
1. How do your points compare with the standard data points
Discussion of Error
1. Calculate % error for two of your points.
2. Discuss possible sources of error. Be specific.