UV Beads and Temperature

Question

How does temperature affect chemical reactions that involved UV radiation?

Hypothesis

My hypothesis is that the UV beads will take longer to reach their full color in the cold and take longer to lose their color. I feel the opposite for the heat. I believe this will happen because in the cold weather things tend to move slower, so the vibrant color will happen slower and losing it will happen slower.

Procedure

• 1. I gathered materials; UV beads (Red, orange, yellow, green, blue, purple, pink) , microwave, mini glass bowl, freezer, thermometers, plastic bags and timer.

  2. I had a timer ready for when testing the beads.

  3. I put three beads of each color in a plastic bag and let the cold (freezer) and room temperature (any room) beads sit in the temperature they will be tested in for 30 min.

     1. For the hot beads, I put the beads in a glass bowl for 30 seconds and then took them out and waited 30 seconds to test their temperature because things cooked in the microwave continue cooking from 30 - 60 seconds after taken out.

  4. I measured the temperature of room or water and immediately took them outside.

  5. I timed how long they took to reach their fullest color.

  6. I took them inside and reset the timer to time how long they took to become clear again.

  7. I did not do all seven beads at the same time so I repeated this times as many times needed until I had tested every color in every temperature.

Conclusion

Shown by the data, my hypothesis was correct. This was because I thought that the color would stick around longer in the cold and it did. The number of more seconds to go to clear for the cold is much larger than the other numbers at 277. The next was room temperature and then the heat. I believe my experiment was accurate because I was very careful when timing and taking the temperature for the beads. One thing the would make this experiment more accurate would be to do it in a lab with UV lights that were always the same temperature.

Abstract

Ultraviolet Radiation

How does temperature affect chemical reactions that involved UV radiation? This is the question I chose to investigate in my science fair experiment. To do this, I used ultraviolet beads, beads that have a pigmented color that will appear under any ultraviolet light. Most of the ultraviolet (UV) light produced by the Sun is blocked by the atmosphere, however some UV light continues to reach Earth. I believed that the UV beads will take longer to reach their full color and longer to lose their full color in the cold than in the heat. I believe this will happen because in the cold weather, things tend to move slower, so the vibrant color will happen slower and losing it will happen slower.

The first step to this experiment was to gather the materials I needed, three ultraviolet beads of each color ( red, orange, yellow, green, blue, purple and pink), plastic bags, microwave, freezer, thermometers, timer, glass bowl and water. The next thing I did, which was for the room temperature and cold beads, was put the beads in plastic bags and let them sit in the temperature for 30 min. For the hot beads, I took a glass bowl and filled it with water. I heated the beads in the water for 30 seconds in the microwave, then took it out and let the water sit for 30 seconds. I did this because liquids in microwaves continue cooking for about 30 seconds to 1 min after being in the microwave. Then, I measured the temperature of the room, water or freezer. I took the container (bowl or bag) outside and timed how long the beads took to reach their full color, then took them inside to see how long it took them to go back to white. I repeated this experiment 7 times for each temperature with three beads.

To find my conclusion, I subtracted the time the bead took to become its color from the time it took to become white. Then, I averaged that information for every color to get my final result. In my data, the information from the room temperature beads proved that on average, it took 173 seconds more time to go clear when the sunlight then it took for the beads to get to full color in sunlight. From the heated beads, it took 155 seconds more time to go clear when the sunlight then it took for the beads to get to full color in sunlight. In the cold, it took 277 seconds more time to go clear when the sunlight then it took for the beads to get to full color in sunlight.

Shown by the data, my hypothesis was correct. This was because I thought that the color would stick around longer in the cold and it did. The number of more seconds to go to clear for the cold is much larger than the other numbers at 277. The next was room temperature and then the heat. I believe my experiment was accurate because I was very careful when timing and taking the temperature for the beads. One thing the would make this experiment more accurate would be to do it in a lab with UV lights that were always at the same temperature.

Graph and Data Table