Life Means Water Environment
ALGIMUNTAS VAILOKAITIS Chicago Board Of Education
1819 Pershing Road
Chicago IL 60615
312 535-8523 X 7838 Mr. Mamrock; Mrs Taylor
Evergreen Academy/312-535-4836 Mr.Laz
James Ward 56th St.; Perez; James Ward Shields Av
Program at Perez; Gunsaulius; Kelly; Delgado
Objective:
1 To understand pH levels in bodies of a water environment. This demonstration
involves the reaction of oxide when mixed with water creates an acidic
solution.
2 To understand the Bronsted-Lowry approach of proton transfer in acid-base
reactions.
3 To understand how sulfur burns in the air and water environment to create
acid.
4 To use hands-on color coding to understand pH and the effect of pH drops
on aquatic life in a healthy lake.
5 To demonstrate scientific method.
Materials:
-heatplate
-coal For students
-erlynmeyer flask -plastic bowls
-eye dropper -salamander (gummyworms)
-universal indicator -snails (malts balls)
-deflagurating spoon -tadpole shrimp (mints)
-stopper -bacteria (good&plenty)
-ammonia -plankton (green leaf mints)
-water -trout (gummy fish)
-pH chart of aquatic environment
-acetate -walleye pike
-coal -jello (royal red)
-3M NaOH -fishing poles (clothespins)
-3 tubes primary colors -toothpicks
-sulfur -plastic cups
-vials -unknown oxide
-white paint -plastic covers
-litmus -small paintbrushes
Strategy:
Begin with process question of what does water environment mean to your
students. Establish the necessity of clean water and it's uses such as
drinking, bathing, cooking. Reflect on how fortunate we are to a big lake and
have a supply well taken care of. Today we are going to introduce a new student
named earl-n-meyer as a student who is a bit shy. Let's warm him up by saying a
few nice words to make him feel welcome.(teacher's note prepare a solution of
100ml water .5ml phenoylphelline with .05ml ammonia to create a pinkish color.)
Dialogue with the class. Ask class for welcoming thoughts. After dialogue,
students will notice change in color. Explain that this is due to an oxide
reaction in water to create an acidic. Explain that, the carbon dioxide in your
breath makes a reaction to form a more healthy pH level in erlynmeyer's body of
water. Use a couple of drops of ammonia to show how the pH again changes to
pink because of the transfer of hydrogen molecules. Here mention that Bronsted-
Lowry demonstrated their theory of proton transfer. Show on overhead
projector how in an acid-base reaction as hydrogen transfer's with water to
produce a new color. Write formula of CO2+H2O-->CO+ H3O, mention as hydrogen
goes up pH's go down. As pH goes up the solution becomes more base. Define an
acid as H+proton donor and base as H+proton acceptor. Write simple equation of
(A :) + B--->C +( D : )
acid acid stronger
Equilibrium is reached when reverse equation happen's often. Notice that as the
pH goes up ! the solution becomes more basic. The reciprocal reaction is that
when the hydrogen +proton goes up ! the solution becomes more acidic.
Introduce a simple demonstration of another acid-base reaction to change pH-
levels with sulfur. Explain that burning coal is another oxide that creates a
pH change. Burn sulfur in a deflagerating spoon. Place into flask with
distilled water along with universal indicator and 2 drops of 3M NaOH. Observe
as the color from purple to blue-green to yellow to orange to red. Ask students
what they think happened. Mention that the protons were donated more rapidly to
hint that the acceptor is the final result (acidic).
Introduce the pH chart with color coded pH levels. In this chart show how
the effects the aquatic life living there. Using vials of paint mixes have
students go to their desks and make their own collection devices or fishing
poles. Give students one vial of each paint mixer and standard white paint
container. Have students mix with toothpicks each vial into a separate ketchup
container or plastic container. Following with the chart ask them to make. a pH
indicator. Then give each student one cup of cold water and piece of litmus
paper to see effects. Ask them to notice how vials marked 1 to 7 create
different pH levels and explain which is more of a base or acid. Now have
students collect their death of a lake jello cup. Pass out the clothes pins
with spoons and have them make collection devices.
Now ask students to pick out each species of aquatic life as pH level goes
down in their lake and count number of species. On acetate paper show a simple
pH graph of lake population as pH goes down. Give hand-out to write or
calculate the number of aquatic life that exist in their lake and pH levels.
Ask students how they might solve the problem of acidic levels of water.
Give students a mission by preparing cups of jello with salamanders (gummy
worms), snails (malts balls), tadpole, (mints), bacteria, plankton (green leaf),
trout and walleye pike (gummy fish), fishing poles (clothes pins and spoons),
and paint sticks. Pass out sheets of instructions to record level of acidity
that makes life unhealthy.
Remind students by collecting the species before time runs out. They still
can be healthy foods. Use 15 minute deadline and ask which species they would
remove first.
Scoring Rubric;
5 Points: Exemplary Response: The color chart shows correct pH. The
explanation of pH is clear. The order of timed removal and species number is
correct. The proof of unknown flask pH's effect on aquatic life.
4 Points: Satisfactory Response: The color chart shows correct pH. The
explanation of pH needs a bit more clarity. The timed order is correct. The
proof of unknown needs direction.
3 Points: The color chart shows correct pH. The explanation of pH is vague The
timed order in another sequence. The proof of unknown needs direction.
2 Points: The response does not answer or explain pH. The timed order in
another sequence with the unknown is incorrectly explained.
1 Point: The response is insufficient and timed sequence.
O Points: blank page
Conclusions: thank GOD for each day.
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