THE BARKING DOG REACTION

The Barking Dog demonstration is based on an exothermic reaction between nitrous oxide (N2O) or nitrogen monoxide (NO) and carbon disulfide (CS2). Ignition of the mixture in a long tube results in a bright blue chemiluminescent flash, accompanied by a characteristic barking or woofing sound. 
 What is happening in this demonstration is a redox reaction where the oxidant is the CS₂ and the reducing agent is the NO or N₂O. The reaction releases a lot of gas (N₂, CO₂, SO₂), which produces the woofing sound, elemental sulphur (S₈) which leaves a yellow layer covering all the tube inner part, and a lot of energy (bright blue chemiluminescent flash).

                        4 NO + CS₂ -> 2 N₂ + CO₂ + SO₂ + 1/8 S₈