Do Now
Tape in “Vocabulary for Quiz 11” onto the
next open page of your comp. book.
Glow Stick Chemistry
Glow Stick Chemistry
1.Turn to the next open page of your
composition book.
2.Title the page “Glow Stick Chemistry Lab”
3.Add the title to your table of contents
4.Write this underneath the title:
Question: How does the surrounding
temperature of a glow stick affect the
intensity of the glow?
Independent Variable: ______________
Dependent Variable:_________________
Controls:__________________________
Ask the Question
How does the surrounding
temperature of a glow stick affect
the intensity of the glow?
Glow stickVariables:
What is the Independent Variable for
this experiment?
IV: The surrounding temperature of the glow stick.
What is the Dependent Variable for
this experiment?
DV: How bright the glow stick is.
What are the constants?
Constants: Beaker, thermometer, glow stick, and amount of time.
Background Research
• A glow stick is
made up of a
plastic tube with
a glass vial in it.
• When you bend
the plastic, you
break the glass
vial, allowing the
chemicals to mix!
Background Research
• A compound
called Hydrogen
Peroxide is inside
the glass vial.
• Two chemicals
are outside the
vial: Phenyl
Oxalate Ester and
Fluorescent Dye
Solution.
Background Research
• When the compounds mix, a chemical
reaction occurs.
• This releases energy and causes the
fluorescent dye to glow (same as a firefly).
• The faster the reaction occurs, the brighter
the glowstick. When the reaction is over, the
glowstick stops glowing!
• Temperature affects the reaction. Today we
will find out how temperature affects how
bright a glowstick will glow.
Hypothesis
Write down your hypothesis underneath the variables in
your comp. book.
Remember to use an “If ------- then ----- “ format.
For example:
If the outside temperature is
warm, then the glowstick will
be _______. (brighter?
dimmer?)
Data Table
Create a data table under your hypothesis in
your comp. book.
Group: ____
Beaker
Temp. (oC) Brightness
(3 = brightest, 2 = second
brightest, 1 = dimmest)
Control (air)
Hot (hot H2O)
Cold (ice)
Conduct the Experiment
• Fill beaker with 1 cup of :
(ice OR hot water OR air)
on the table
• When directed by your
teacher, break the glow
stick and place it in the
beaker at your desk.
• Measure the temperature
in your data chart (for your
experimental group)
• Once the glow stick is in
the beaker, do not touch it!
Taking Temperature Readings
1. Carefully lower the bulb
end of the thermometer
into the beaker.
2. Hold the thermometer so
its bulb is near the center
of the beaker.
3. Record the temperature
into your data table.
Compare Variables
• When directed to, send your data
manager to compare your glow stick
with two other temperature groups in
your class and record results in your
data table.
• Make sure you get their temperature
data too!
• If your glow stick is the brightest, write
down “3”, if it is the 2nd brightest, write
“2”, and if it is the dimmest, write “1”.
Analyzing Data and Graphing
• When asked to, enter your data in
the excel chart at the front of the
room.
• Choose “3” for the brightest, “2”
for the 2nd brightest, and “1” for the
dimmest.
•
Drawing Conclusions
Use complete sentences to Answer conclusions in
your comp. book.
CONCLUSION:
1. Was your hypothesis supported or rejected?
2. Explain your answer to question #1 using data.
3. How does the surrounding temperature of a glow stick
affect the intensity of the glow? Use the data to
support your results.
4. What are some human errors that could have affected
your data?
EXPLANATION:
1. How did the research support your results?
FURTHER QUESTIONS:
1. What are some further questions?