Sciencemadness Discussion Board

Temperamentality of the 'Barking-Dog' reaction

Ozonelabs - 7-9-2008 at 14:26

Whilst demonstrating the Barking-Dog reaction, Ozonelabs found that the reaction was very temperamental. Two literary references showed the reaction using Nitrogen Monoxide and the other using Nitrous Oxide.
Ozone labs has found that using Nitrogen Monoxide gave little effect and the Carbon Disulphide merely burnt on top, not giving the desired 'Bark'.
Ozonelabs was wondering if anybody else has had experience with this reaction using Nitrogen Monoxide?

Thank for your time

12AX7 - 7-9-2008 at 17:10

Have you asked Bob Dole if he's run this experiment?

Tim

DJF90 - 8-9-2008 at 02:20

I thought the barking dog experiment was with white phosphorus dissolved in carbon disulphide...? Thats how we did it at a uni open day :P

ScienceSquirrel - 8-9-2008 at 04:18

I have only seen the barking dog reaction run with nitrous oxide.

The most convenient way to do it on a demonstration scale is to use a cream whipper to dispense the nitrous oxide.
They use small bulbs similar to Sparklets carbon dioxide bulbs and are fairly readily available.

woelen - 8-9-2008 at 08:46

I have done this experiment some time ago, exactly in the way as DJF90 describes, with N2O from a whipped cream dispenser.

http://woelen.homescience.net/science/chem/exps/barkingdog/i...

EDIT by woelen: Changed link, so that it works again.

[Edited on 12-6-12 by woelen]

DJF90 - 8-9-2008 at 10:22

The way we did it is slightly different. A long gas jar is covered with a filter paper. Onto this is placed some white phosphorus dissolved in carbon disulphide. The carbon disulphide permeates the filter paper and its vapor saturates the gas jar. Once the majority of the carbon disulphide evaporates the white phosphorus reacts withh the oxygen in the air and spontaneously combusts. The vapor in the gas jar then ignites and burns rapidly, producing a barking sound as it does so. I guess this is the same experiment but a different means of doing it.