There was a funny but interesting email exchange between me and a chemistry professor.
<My question>
Hello, I am a grad student in Dr. Sweedler lab. I came up with an interesting idea while I was resting, and I want to informally ask you a question.
My question is .. Are there chemicals that emit sound of specific wavelength as they burn ? I am wondering if I build a candle or firecracker that can play 'Happy Birthday' song as they burn through.
Let me know.. Thanks..
<Reply>
The pitch of sound is determined by the resonance of the surroundings NOT by any choice of chemicals. I think you must be thinking of the “barking” or “whooping dogs” demo which places white phosphorus (P4) in CS2 on a piece of filter paper sitting on top of a large graduated cylinder. As the CS2 evaporates, the white phosphorus reacts with air and sets the filter paper on fire, which sucks O2 out of the cylinder and that generates the whooping noise as air then refills the partial vacuum in the cylinder.
https://books.google.com/books?id=0rx6Cjx_l-AC&pg=PA75&lpg=PA75&dq=%22white+phosphorus%22+cylinders+sound&source=bl&ots=tjniaxJQeX&sig=ACfU3U2GqAGbMyjaPE4Ooiv677rTrf4pTA&hl=en&sa=X&ved=2ahUKEwiK-viku6HnAhXCK80KHSmNAYEQ6AEwC3oECAcQAQ#v=onepage&q=%22white%20phosphorus%22%20cylinders%20sound&f=false
https://www.chemicalforums.com/index.php?topic=212.0
This is a pretty hazardous demo and I would NOT recommend it for a birthday party. Besides you’d need way too many different cylinders tuned to the right size to play a happy birthday tune. Not to mention copyright issues ;^)
--Ken
Kenneth S. Suslick
Marvin T. Schmidt Research Professor of Chemistry
University of Illinois at Urbana-Champaign
<My reply>
Thank you for the really great information. Actually, I saw the candles playing songs in my dream while I was taking a nap on Saturday, and I wondered if I could do something about the idea & reached out to the expert.. If so I will just record about the idea on my note and move on. Really appreciated. Have a good day.
