Unexpected light from some reactions

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Experiments investigating the interaction between sodium hydroxide and various molecules, including water and formaldehyde, have resulted in the unexpected emission of light. While the Cannizzaro reaction involving formaldehyde and NaOH is known to produce intermediates that undergo energetic transitions, the exact mechanism behind the light emission remains unclear. The equipment used is not sensitive to thermophotons, suggesting that exothermic reactions are not the primary source of the observed photons. The emitted light is primarily in the green-blue spectrum, and different combinations of reactants have been tested, consistently producing light, albeit at varying intensities. Notably, substituting sodium hydroxide with potassium or barium hydroxide resulted in no light emission. Additional reactions, such as mixing hypochlorite and sodium ascorbate, also produced light without significant heat production. The discussion highlights the need for further investigation, including the potential use of spectrometry to analyze the emitted light's frequencies and identify the chemical bonds responsible for the phenomenon.
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dear all,
in a series of experiments on the interaction between sodium hydroxide and other molecules such as water, Triton X-100, formaldehyde and others, we found emission of light. Besides the formaldehyde-NaOH interaction, i.e. the Cannizzaro reaction in which some intermediates may form undergoing highly energetic transitions, we have no useful ideas of the mechanism reponsible for such light emission. Our equipment is insensitive to thermophotons, so the exothermicity of the above reactions as the primary source of measurable photons should not be directly involved. Aiming to go more in depth into the aforementioned phenomenon, please consider this post a call for suggestions and/or partnership.
thanks,
Leopoldo Silvestroni
 
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could you use a spectrometer to determine their frequencies and thereby what series they might belong to baumann. lyman...? Maybe that would help determine the chemical bond that was creating the light.
 
jedishrfu said:
could you use a spectrometer to determine their frequencies and thereby what series they might belong to baumann. lyman...? Maybe that would help determine the chemical bond that was creating the light.

I don't know much about physical chemistry. What is the baumann series? Do you mean Balmer series?
 
jedishrfu said:
could you use a spectrometer to determine their frequencies and thereby what series they might belong to baumann. lyman...? Maybe that would help determine the chemical bond that was creating the light.

Roughly, emitted light is in the green-blue region, as assessed by a photomultiplier tube close to the reaction vessel with (broad band) thin plastic filters in between
 
Have you tried removing substances to see if you get the same behavior with fewer reactants?
 
Reptillian said:
Have you tried removing substances to see if you get the same behavior with fewer reactants?

yes. water-NaOH, water-TritonX100, formaldehyde-NaOH are some examples. Light was produced in all the above reactions, though with different intensities (photons per sec)
 
Is the total light intensity equal to the sum of the intensities from the individual reactions? I'm assuming these are exothermic reactions? If so, could this be due to increased radiation (blackbody) from the increase in temperature?
 
I assume that all of these experiments were conducted in absolute darkness?
 
pa5tabear said:
I don't know much about physical chemistry. What is the baumann series? Do you mean Balmer series?

Yes balmer series, my bad memory, sorry.
 
  • #10
Reptillian said:
Is the total light intensity equal to the sum of the intensities from the individual reactions? I'm assuming these are exothermic reactions? If so, could this be due to increased radiation (blackbody) from the increase in temperature?

I'm referring to individual reactions only. The "simplest" example is dropping water onto solid NaOH. Which excited intermediates relaxe with photon emission in our spectral window? (our photomultiplier tube has a 330-550nm spectral sensitivity).
Note: when potassium hydroxide or barium hydroxide are substituted for NaOH, NO light is produced.
Light emission comparable to the above also occurs in the more complex and intermediate-rich formaldheyde-NaOH reaction (i.e. Cannizzaro's reaction).
Moreover, light emission is also produced upon mixing hypochloride and sodium ascorbate solutions, a reaction occurring without apparent heat production.
 
  • #11
chemisttree said:
I assume that all of these experiments were conducted in absolute darkness?
Ground signal from our apparatus is always below 30-50 photons per sec. The cited reactions give a photon output of even dozens of thousands of photons
 

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