What happened was that the heated sulfur bonded with the surrounding oxygen to produce sulfur dioxide (SO2) and sulfur trioxide (SO3). Both of these products are poisonous and here is the interesting reason why. These gases bond with water molecules in the air, or on the surface of your body, to form both sulfurous acid (H2SO3) and sulfuric acid (H2SO4) on the spot! While this reaction isn't extremely dangerous, it should obviously be performed outdoors or in a fume hood. In my opinion, sulfur is a fascinating element with many unique aspects.
If you would like to learn a bit more about sulfur...



