In the spirit of Halloween each year, I do some really fun ‘spooky’ labs in my chemistry class. I have the students fill out a worksheet that explains why the chemistry behind these awesome experiments, and then we do some exciting exploration of different topics. I enjoy it because they always get really excited about science!
In the past, I have shown my class some household items that fluoresce.
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| Mr. Clean, Tonic Water and Vitamin B dissolved in Water |
I also have them draw pictures with Magic Marker and Highlighter and then shine a black light on it to show the difference.
This year I decided to expand my black light experiments! I had heard about using highlighters to make regular flowers fluoresce and I really wanted to try it!
What you’ll need: A black-light, highlighter(s), white flowers, kitchen shears and a vase 🙂
Step 1: First, I cut the highlighter in half using kitchen shears.
Step 2: Then I took out the ink from the highlighter and put it in a vase of water. This part was a little messy! The ink washed off with soap, however, when I turned on the black light my hands showed evidence of the highlighter spill!
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| Hand in normal light |
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| Hand under black light |
Step 3: The ink started dissolving into the water right away, but I did stir it around some. I decided to leave my highlighter ink pad in the water for extra absorption.
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| Highlighter Ink in Water |
Step 4: Then I cut some flowers that I got at the grocery store and placed them into the vase! I wanted to use carnations, but the grocery store didn’t have any, so I bought three varieties of white flowers. Daisies seemed to absorb the most color, however, all three varieties did! {Update: I’ve repeated this experiment many many times and daises definitely have done the best overall!}
Step 5: Then the hardest part of the experiment began- I had to wait! The example I had heard about said it would take about two days. However, being impatient, I decided to check my flowers after about 30 minutes. The daisies had already began to absorb highlighter!! The flowers didn’t change color to the naked eye, but they certainly looked cool with a black light! After about three hours they reached their full fluorescent power- even the leaves started to show signs of highlighter!
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| In Normal Light |
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| After 15 minutes in Black Light |
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| After 3 hours in Black Light |
Kai and Naeco were also really interested in the lab- or it may have been because I don’t normally pay to have fresh cut flowers in the house 🙂
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Here are some more pictures of my AWESOME flowers! I think they turned out really neat! |
You can check out a video of some of my other Halloween science labs here:
Or, if you want a full list of all the Spooky Labs (including worksheets and directions) visit my Teachers Pay Teachers page! http://www.teacherspayteachers.com/Product/Halloween-Science-Labs-944305
I hope you have a wonderful Halloween! And get an opportunity to do some ‘spooky science’ 🙂
