Is this reaction to produce ammonium sulfide safe?

For my chemistry experiment, I was assigned to produce ammonium sulfide and test the chemical properties of the compound. From my online research, I found out that I can mix household ammonia and match heads to produce Ammonia Sulfide.

I think this will satisfy the purpose of my assignment, but I have a few concerns.

I'm not sure what proportions I should mix these materials in order to produce an ideal solution. I am also unsure about the exact results of mixing ammonia and match heads, since match heads consists of more than just sulfer, but also potassium chlorate, antimony trisulfide, and some oxidizing agents. Will the end product potentially be dangerous? I plan to mix the two chemicals in a enclosed test tube, and seal it for a few days.

• The name of the compound you are planning to make is ammonium sulfide. Ammonia ($\ce{NH3}$) is a gas under standard conditions. Household ammonia is a solution of this gas in water. If you increase the temperature, the gas will boil off. Keeping the mixture in a sealed test tube might not be the best idea then. If you are uncertain about possible health effects, it is always a good idea to have a look at the material safety datasheet (MSDS)! – Klaus-Dieter Warzecha Apr 1 '14 at 9:31
• You didn't mention whether you just want a solution or your product as a solid. Have you considered an alternative route: Generate hydrogen sulfide in a Kipp's apparatus and run it into household ammonia? In any case: Fume hoods are a great invention! – Klaus-Dieter Warzecha Apr 1 '14 at 9:49
• I just want to make the solution and observe the characteristics of the solution. – user5037 Apr 2 '14 at 22:35
• General rule: If you have to ask "Is it safe?", it's probably not. – Todd Minehardt May 25 '16 at 1:10

$$\ce{H2S(aq) + 2 NH3(aq) -> (NH4)2S(aq)}$$

Upon mixing ammonia with potassium chlorate:

$$\ce{KClO3(aq) + NH3(aq) -> NH4ClO3(aq)}$$

$$\ce{Sb2S3 (aq) + NH3(aq) -> Sb(OH)3(s)}$$

Sb(III) reacts with aqueous ammonia to precipitate white Sb(OH)3. MSDS sheets say that antimony trisulfide is:

Toxic to aquatic life with long lasting effects.

Furthermore:

$$\ce{Sb2S3(aq) + (NH4)2S(aq) -> (NH4)3SbS3 (aq)}$$

• You used potassium chloride instead of potassium chlorate. – LDC3 Apr 1 '14 at 0:53
• @LDC3 Ah, thank you. I'll go ahead and fix that. – Jun-Goo Kwak Apr 1 '14 at 1:04
• I go to a charter's school, and the curriculum is very hands on and open. I actually volunteered to do this experiment because I actually can get my hands on these materials. What do you mean taht it's toxic to aquatic life? It will only be exposed to me when I test it. I'm just hoping it won't harm my health in some serious ways. I will make sure to work in a ventilated area in case anything happens. Do you think if that's enough precaution? – user5037 Apr 1 '14 at 3:29
• I am downvoting this because most of the presented equations are wrong. Only starting with your ammonia has an extra $\ce{H}$. Check this and edit it. – Martin - マーチン Apr 1 '14 at 6:05
• For your ammonium you were missing a charge ;) I would strongly suggest that you again revisit your equations and balance them. (I'm sorry, I just want to help.) I think it is okay to sometimes leave out byproducts, but since this is clearly a question asked by a non-expert, I would not leave room for mistakes. – Martin - マーチン Apr 2 '14 at 2:20

In fact there are many types of matches so you should be aware of what you are using. In home-made experiments the problem is that many times you don't know the composition or the concentration of your reactants.

Take a look a The Preparatory Manual of Black Powder and Pyrotechnics by Jared Ledgard for understand the composition of your matches.

We can assume that you have 20-50% of potassium chlorate and if present 1-15% of sulfur. I don't know the weight of a match's head (if someone have a laboratory balance you could determine it) however I think surely it weights no more then 4 mg. So in 50 pics matches box you have max 0,2 g of heads matches. So 0,1 g of potassium chlorate and 0.06 g of sulfur.

Hydrogen sulfide

Hydrogen sulfide is toxic and so can be dangerous but assuming that all the sulfur became hydrogen sulfide you have $0.06g_{Sulfur}~/ 32 \frac{g}{mol}=0.001875~mol$ of $H_{2}S$ hence $$0.001875~mol \times 34.08\frac{g}{mol}= 0.0639 g$$ of Hydrogen sulfide. So if you work in a room of $4~m \times 4~m \times 2~m$ so $32 m^{3}$ you have 1.9 $\frac{mg}{m^{3}}$ of hydrogen sulfide according to EPA is above the LOAEL (HEC): 1.9 $\frac{mg}{m^{3}}$ dose. However I hope that you will to the experiment in a well ventilated ambient. In this condition I think that is safe, however I don't think is a good experiment to perform.

Chlorine

Assuming that the chlorine in potassium chlorate is release as chlorine with a 100% yield (I'm quite sure that this can't happen) you have:

$$0.1g_{KClO_{3}} / 122.5495 \frac{g}{mol}=0.00082 mol_{KClO_{3}}$$

Hence, 0.00041 mol of $Cl_{2}$ and so if 70.9 is the molecular weight 0.029069 g of chlorine.

So in a $32 m^{3}$ "room" you have 0.90625 $\frac{mg}{m^{3}}$ of chlorine according to EPA is below the LOAEL 1.2$\frac{mg}{m^{3}}$ dose.

P.S. Up to my knowledge $\ce{Sb2S3}$ is no more used.

• It is also to my understanding that Antimony is not used any more. People understood the hazardous nature of Arsenic and Antimony is many times worse... – Martin - マーチン Apr 1 '14 at 10:56