vmelkon - 29-7-2014 at 15:11
Does naphthalene glow blue under ultra-violet light or am I imagining things. I have a mercury vapor lamp that I use to check out various substances
for fluorescence.
It looks like it is emitting as much blue light as paper and white cloths.
Artemus Gordon - 29-7-2014 at 16:35
Could be. Wikipedia <a href="http://en.wikipedia.org/wiki/Fluorescence#Organic_liquids">says</a>:
"Organic solutions such anthracene or stilbene, dissolved in benzene or toluene, fluoresce with ultraviolet or gamma ray irradiation."
Since anthracene is 3 fused benzene rings, and naphthalene is 2 fused benzene rings, I'd say there is a good chance you are right.
[Edited on 30-7-2014 by Artemus Gordon]
unionised - 30-7-2014 at 10:52
It does fluoresce, but very little of that emission would be visible.
http://omlc.org/spectra/PhotochemCAD/html/001.html
However, commercial naphthalene might contain anthracene etc as an impurity.
A further complicating factor is that a mercury lamp also emits some visible light and the naphthalene might be just reflecting that.
Can you compare it against something like salt which does not fluoresce?
[Edited on 30-7-14 by unionised]