1. Introduction Video: Glow sticks
These are not the glow sticks I used, but this is just to show you the effects of chemical reactions and thermochemistry….

2. Angela Sun May 2nd, 2014 Period 6 Science Discovery project
Let it Glow How does temperature affect the glow time of glow sticks? Thermochemistry
Angela Sun
May 2nd, 2014
Period 6 Science
Discovery project

3. Field Introduction Thermochemistry: Why I Chose This Project: VS.
branch of thermodynamics and chemistry that deals with the relationship between chemical action and heat.
study of heat transfer during reactions and processes, whether those may be physical or chemical reactions.
Why I Chose This Project:
curious to find out if temperature had anything to do with chemistry
Observed that glow sticks were brighter on 4th of July than Halloween and wanted to find out why.
VS.

4. Opportunities Career: Thermodynamics Technology Specialist:
Uses knowledge of chemical engineering, thermodynamics, physical properties of fluids, and phase equilibrium behavior of complex fluid mixtures.
Experiment utilizes fluid mixtures and thermodynamics

5. Timeline 1895- Discovery of Luminol:
two scientists named Wiedemann and Schmid dissolved cathode-ray irritated alkali halides in water.
weak bluish light.
In 1928, the German chemist, H. Albrecht, accidentally discovered that by adding hydrogen peroxide to luminol, the reaction would cause the mixture to glow a green -blue color.
Relation: glow stick components
1960- Invention of the glow stick:
chemist of Bell Labs, Edwin A. Chandros first discovered that a glowing chemical light was produced when fluorescent dye and hydrogen peroxide was mixed with oxalyl chloride.
Impact society: no electricity, cheap, no toxic chemicals=safe
Relation: glow stick=main part of investigation

6. Experimental Design Diagram
Title: How does temperature affect the glow time of glow sticks? Hypothesis: If the temperature is 65°C, then the glow time of the glow sticks will decrease because the atoms in the chemical solution inside the glow stick will start moving faster, hence using the stored chemical energy faster but producing a brighter light.
Independent/Manipulated Variable:
Temperature (Celsius or °C)
Levels of MV:
5°C
20°C
35°C
50°C
65°C
Number of Trials: 3 3 3 3 3
Dependent/Responding Variable:
Glow time (Minutes)
Controlled Variables:
Glow stick brand, glow stick age, glow stick color, glow stick size, type of thermometer, stopwatch, size of beaker, brand of beaker, amount of water in beakers, location of investigation

7. Background Research
Glow sticks glow due to the chemical reaction called chemiluminescence.
Glow sticks consist of only two parts:
an inner glass vial and the outer plastic
tube. Glow sticks contain two
chemicals and a fluorescent dye.

8. Experimental Set-up Labels Beakers Stove Thermometer Ice 5°C label
Glow stick
Beaker
Syringe
Thermometer
Roll of masking tape
Permanent Marker
Beaker
65°C label
Glow stick
Stove

9. Safety
Be careful not to burn yourself with hot water and hot plates. Gloves highly recommended.
Do not touch broken glass.

10. How does temperature affect the glow time of glow sticks?
Data table
How does temperature affect the glow time of glow sticks?
Temperature (°C)
Time (min) 1 2 3
Average
5°C
4630
5002
6626
5419
20°C
2975
1846
3048
2623
35°C
707
643
868
741
50°C
650
814
728
730
65°C
560
696
673

11. Observations
Even in the beginning, freshly cracked glow sticks started out with different shades of neon yellow.
Glow sticks in hotter water had less viscous chemicals inside.
Glow sticks in hotter water glowed more brightly but lasted a shorter time, and vice versa for glow sticks in colder water.
The glow of the sticks slowly faded and became dimmer instead of stopping abruptly.
Each glow stick had a different level/shade of neon yellow.

12. Graph

13. Conclusion How does temperature affect the glow time of glow sticks?
Hypothesis: (data does support)
If the temperature is 65°C, then the glow time of the glow sticks will decrease because the atoms in the chemical solution inside the glow stick will start moving faster, hence using the stored chemical energy faster but producing a brighter light.
Claim: As temperature increases, glow time decreases.
Evidence:
Reasoning:
Heat speeds up chemical reactions
Particles only react due to collision, more heat = faster moving particles = collision frequency increase = reaction rate increase
Faster chemical reactions use up chemical energy in glow stick more rapidly = brighter glow
Temperature (°C)
Average glow time (minutes)
5°C
5419
20°C
2623
35°C
741
50°C
730
65°C
643
*Connect to introduction research

14. Applications Experimental Design Improvement:
hot plates that had adjustable temperatures so that temperatures could always be maintained.
helpful so that the results are more accurate
Future Experimental Design:
how does glow stick color affect glow time?
help society because if certain glow stick colors glowed longer than others with the same amount of chemicals, then more glow sticks of that color(s) would be produced
Real World Application:
deep sea divers
Glow sticks can withstand a lot of pressure from beneath the ocean/sea, are waterproof, and also will not electrocute users since glow sticks don’t need electricity to function in the first place

15. Disadvantages (Cons):
Personal reflection
Advantages (Pros):
Disadvantages (Cons):
Create new ideas and theories for society.
Fairly low salaries
Develop new creations
Many years of college
Choice on work:
Labs
Field work
Writing or teaching
Extensive career options…
Hazardous risks:
Sir Humphrey Davy nearly killed himself many times.

16. Work Values Help Society: 2. Profit, gain: 3. Location:
Contribute to the betterment of the world I live in.
Discover something new, can contribute greatly
2. Profit, gain:
Expect to earn large amounts of money or other material possessions.
Chemists don’t make much money
3. Location:
Find a place to live (town, geographic area) that matches my lifestyle and allows me to do the things I enjoy most.
Can work in different places and environments,
outdoors, classrooms, etc.
Chemistry is still an intriguing field, outcomes
Never expected.