Sciencemadness Discussion Board - What's this weird blue-white flash in the middle of a dry ice water bottle explosion

What's this weird blue-white flash in the middle of a dry ice water bottle explosion

deltaH - 7-1-2015 at 04:43

I was watching this slow motion video of dry ice in water bottle explosions:

https://www.youtube.com/watch?v=t6X0HTOKC24

and was wondering what cause the blue-white fog in the centre for a split second when it blows. I've included a still of the moment this appears for clarity:

phlogiston - 7-1-2015 at 05:26

It appears related to a pressure wave that reflects of the remains of the casing. Possibly, it triggers nucleation/condensation of water vapor or CO<sub>2</sub>.

careysub - 7-1-2015 at 05:26

It is simply the CO2 "smoke" (dense water vapor fog) that filled the bottle's air space before it burst.

deltaH - 7-1-2015 at 05:52

It forms from the outside-in as phlogiston points out, moments after the explosion. It also disappears a tiny fraction of a second later.

[Edited on 7-1-2015 by deltaH]

careysub - 7-1-2015 at 06:05

Quote: Originally posted by deltaH

It forms from the outside-in as phlogiston points out, moments after the explosion. It also disappears a tiny fraction of a second later.

[Edited on 7-1-2015 by deltaH]

Oh, I see. In the earlier test you can see smoke filling the bottle before the burst.

What you are seeing in the slo-mo is the Wilson cloud chamber effect, sudden drop in pressure causing momentary cloud condensation. (Also seen behind the shock wave of large explosions in humid atmospheres).

deltaH - 7-1-2015 at 06:26

Quote: Originally posted by careysub

Quote: Originally posted by deltaH

It forms from the outside-in as phlogiston points out, moments after the explosion. It also disappears a tiny fraction of a second later.

[Edited on 7-1-2015 by deltaH]

This sounds about right, I think this is also what Phlogiston was referring to. Thanks both.

[Edited on 7-1-2015 by deltaH]