Will ammonium sulfide #("NH"_4)_2"S"# decompose when heated? What will be the products?

I can't seem to find the reaction formula online.

1 Answer
Feb 16, 2016

Yes it will.

Explanation:

Ammonium sulfide, #("NH"_4)_2"S"#, will indeed decompose upon heating to form ammonia, #"NH"_3#, and hydrogen sulfide, #"H"_2"S"#, as main products.

Ammonium sulfide will actually begin to decompose at temperatures as low as room temperature.

#("NH"_4)_2"S"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) 2"NH"_text(3(g]) + "H"_2"S"_text((g])#

I think that the decomposition reaction involves the formation of ammonium hydrogen sulfide, #"NH"_4"HS"#, which then decomposes to form hydrogen sulfide.

You can thus say that you have

#("NH"_4)_2"S"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) "NH"_text(3(g]) + "NH"_4"HS"_text((s])#

which then goes to

#"NH"_4"HS"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) "NH"_text(3(g]) + "H"_2"S"_text((g])#

The overall reaction will once again be

#("NH"_4)_2"S"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) "NH"_text(3(g]) + color(red)(cancel(color(black)("NH"_4"HS"_text((s]))))#
#color(red)(cancel(color(black)("NH"_4"HS"_text((s])))) stackrel(color(red)(Delta)color(white)(aa))(->) "NH"_text(3(g]) + "H"_2"S"_text((g])#
#color(white)(aaaaaaaaaaaaaaaaaaaaaaaaaaaaaa)/color(white)(aaaaaaaaaaaaaaaaaaaaaaaaaaaa)#
#("NH"_4)_2"S"_text((s]) stackrel(color(red)(Delta)color(white)(aa))(->) 2"NH"_text(3(g]) + "H"_2"S"_text((g])#

Heating ammonium sulfide in the presence of air will also result in the formation of toxic sulfur oxides and nitrogen oxides as side products.