Name: ________________________________
A__: Mon, Sep 28
B__: Tue, Sep 29
#10 Solubility Lab
Mr. Wegert – Chemistry
Do Now: Read passage, annotate, and answer questions. Turn over sheet, read BOC when done.
Passage #10
Early evidence about the Fish Kill seems to point to something dissolved in the water as the cause.
Theory 1: Pollutant Dumping
Some people think that pollutants being dumped into the river finally killed the fish. The Mining
Company puts pollutants in storage ponds near the river. The Electric Power Company controls the
flow of water in the river, and the last time they released large amounts of water, there was a fish kill.
Theory 2: Excess Rainfall
This was a particularly wet summer before the fish kill, with lots of rainfall. The farmers in the
Agricultural Cooperative use pesticides and fertilizers, which can wash into the river in heavy rain.
1. What’s the early
hypothesis about what
killed the fish?
2. If pollutants got into the
river, where might they
have come from?
3. If something other than
pollutants got into the
river, what might they
have been?
4. What also happened the
last time there was a fish
kill?
5. If it were determined
that disease killed the
fish, which theory would
this support, and why?
CRS Clicker Practice:
Q Claim Evidence (what you see)
1
2
3
4
5
# 10 Solubility Lab
Reasoning (what you think about what you see)
Hypothesis: ________________________________________________________________________
Purpose: __________________________________________________________________________
Solubility Lab Procedure Checklist (in pairs):
 1. Get your group’s hot plate from bottom drawer. Turn on (green light on), set dial on #10.
Place test tubes in white test tube rack (also from your bottom drawer).
 2. Put about 250 ml of tap water from your sink in beaker and place beaker on the hot plate.
Add 15 ml of distilled water to the test tube that has the 5g of white succinic acid solute in it.
 3. Place test tube (with water and white solute) in the water in the beaker on hot plate.
 4. Heat up test tube in beaker on hot plate, stirring occasionally with thermometer inside test tube
(hold test tube with other hand), until target temperature (inside test tube) is reached.
 5. Once target is reached, record the highest actual temperature reached (NOT the
target temperature). Remove test tube and place in rack. Put thermometer in bin.
 6. Turn off hot plate and unplug it.
 7. Decant solution (pour out all the liquid but not the white solute) into a clean test tube.
Take used test tube with undissolved white solute to front of room and put in front sink.
 8. Get one ice water bath beaker for your table from front sink. Swirl test tube with clear solution
in it around in ice water bath to cool it down, but do NOT stir the liquid inside the test tube.
Swirl until white precipitate begins to form, and keep swirling until it stops getting higher.
 9. Record height of white precipitate in centimeters, to at least one decimal place.
 10. Empty both beakers in your sink. Used test tubes and contents go in sink at front of the room.
Hot plates and test tube racks go back in proper drawers. Everything else goes back in bins.
Solubility Lab Results
Lab Pair
Target Temp
1AC
o
70
1BD
o
70
2AC
o
70
2BD
o
70
3AC
o
80
3BD
o
80
4AC
o
80
4BD
o
80
5AC
o
90
5BD
o
90
6AC
o
90
6BD
o
90
Hot Temp.
o
( C)
Precipitate
crystal
height (cm)
Avg. Hot
Temp
Avg. Height
Homework:
1) In this experiment, what about the
temperature was manipulated?
2) In this experiment, what was watched
and measured? What was this measure
supposed to represent?
3) Why was it important for all students to
use the same brand of test tube?
4) What might be a good hypothesis for
this experiment?
5) Honors/EC: Why were several trials
done at different target temperatures?
Homework (write in agenda): Complete worksheet table above
# 10 Solubility Lab
____/10 pts