Add one scoop each of luminol and perborate mixtures and a few copper sulfate crystals to each cup.
Add a consistent amount of each chemical.
Try to count the grains of copper sulfate so that you are adding close to the same amount to each reaction.
As an option, premix the dry ingredients in a clean, dry container. Add enough luminol, perborate, and copper sulfate for 10 reactions. This will minimize variation that could result if you add them separately.
Put the cups with the ingredients on the paper plate on your work surface. The work surface should be waterproof.
Make sure you know how to work your camera and how to set the exposure time. Set up the camera and tripod so that the camera is focused on the two cups. …show more content…
Experiment with taking pictures of the cups in dim light.
For example, try 5-, 10-, and 15-sec exposures in dim light. You want a picture that clearly shows the relative brightness of the two cups. 5. Add 1/3 cup of ice-cold water to a Styrofoam cup. 6. Add 1/3 cup of hot tap water to a second Styrofoam cup. 7. Determine the temperature of the water in each Styrofoam cup. 8. Now add the cold water to one of the plastic cups containing the luminol, perborate, and copper sulfate. 9. Add the hot water to the other plastic cup. Have your helper pour water into one of the containers so that the reactions start at the exact same time. You and your helper should each mix a solution with a clean spoon. 10. Start the stopwatch or timer. 11. Dim the lights and observe the light produced by each
cup. 12. Take a picture of the two cups. Record the time on the stopwatch or timer at which the picture was taken. 13. Continue taking pictures, recording the time at which each picture is taken.
The number taken will depend on the length of the exposure. It is important not to vary the conditions for the pictures once you have settled on an exposure time that works well. A good exposure time should give you a clear picture of the two cups so you can compare their brightness.
You will want to compare all of the pictures later, so the conditions should be as consistent as possible. 20. Repeat steps 3–11 two more times, with clean and fresh materials. Can use same water temperatures or use different ones.
Take pictures at the same time intervals for each trial and using the same exposure length every time.