Sciencemadness Discussion Board

Elusive Reaction

blue_vitriol - 25-4-2013 at 17:37

I have been searching and I cannot fine the products for the following reaction:
Sb2S3 + KOH

elementcollector1 - 25-4-2013 at 18:56

At a guess, and assuming you're roasting the stuff:
Sb2S3 + 3KOH -> 3K2S + Sb(OH)3
2Sb(OH)3 -> Sb2O3 + 3H2O
Or, possibly:
Sb2S3 + KOH -> KSb(OH)6 (un-balance-able)

This is speculation from general knowledge of chemistry (though I did have to look up if there is such thing as an "antimonate ion" on Wikipedia).

woelen - 25-4-2013 at 22:37

The last thing is wrong. You write yourself that this equation is unbalanceable. If an equation is unbalanceable mathematically, then one for sure knows that it cannot occur in reality!

The problem with your equation is that Sb at the left is in oxidation state +3 and at the right it is in oxidation state +5 and besides that, no sulphur is at the right.

Sb2S3 + KOH also can react in aqueous solution. This may lead to thioantimonites (one or more oxygen atoms replaced by sulphur). The Sb2S3, however, must be freshly precipitated (the orange stuff). The black crystalline stuff is more inert and only reacts with KOH with great difficulty, but I'm not 100% sure whether it is completely unreactive or not.

elementcollector1 - 26-4-2013 at 05:27

I didn't think it it would work, but decided to include in the realm of possibility. And then forgot the sulfur. :D