# What would an ammonium sulfide fire look like?

I am writing a novel and the climax involves killing my protagonist in an explosion. My science knowledge is poor but I believe my scenario is entirely plausible except possibly a couple of details.

My character is in a small, poorly ventilated room. It has an equipment or instrumentation cart with some 1970s era machinery. Within it is a jar of ammonium sulfide from which the gas is pumped via leaky tubes. The leak has gotten worse and the room is very smelly. He bends over to unplug the equipment, which is not grounded. The smell is worse near the floor. Pulling the plug out of the outlet causes a spark and the gas ignites.

I hope this is perfectly logical so far. Now here are a couple specific questions.

What would that fire look like? I currently have a line of fire in the air back to the source by the jar. It then explodes. I then have gases like hydrogen sulfide produced and there is a larger, secondary explosion which kills the injured character.

Would it be better to say that all of the gas burns in a flash. Not much damage is actually done, but the jar of ammonium sulfide is heated, begins to produce hydrogen sulfide and other pyrophoric gases and then there is a spectacular secondary explosion?

I am not necessarily going to explain the science to the reader, which gives me some wiggle room. But I do want these events to be plausible.

• It's not clear to me what gas is igniting. If you are imagining the hydrogen sulfide is the gas that ignites your character may have another problem. In that hydrogen sulfide is incredibly dangerous to inhale. As in levels above 100 ppm are regarded as immediately dangerous to life. I guess a ppm level that could be ignited would probably render unconscious kill anyone that walked into that room in minutes. See this terrifying document for more: vinnueftirlit.is/media/greinar-og-skyrslur/… – BiggChemT Nov 21 '16 at 20:54
• Thank for that! I have the ammonium sulfide in the air burn first, then the bottle of the stuff explodes, as it stands now. There is then a secondary explosion Involving the hydrogen sulfide. – Nicholas Palmer Nov 22 '16 at 3:50
• Note that pure ammonium sulfide would basically be a source of H2S, which is toxic via inhalation. I think I've seem quotes where ammonium sulfide at 600 ppm in air caused fatalities. It also REALLY smells bad. I'd guess it would be fatal at levels below those necessary to combust. – AlaskaRon Nov 30 '16 at 4:12

If your container is supposed to contain solid ammonium sulfide $\ce{(NH4)2S}$, it better be cooled to -20 °C or below.