Question

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.

Answer 1

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.