Sciencemadness Discussion Board

Goodbye to S2− in aqueous solution

Joeychemist - 20-3-2018 at 14:14

Abstract

New Raman spectra of Na2S dissolved in hyper-concentrated NaOH(aq) and CsOH(aq) cast serious doubt on the widely-assumed existence of S2−(aq). To avoid conceptual and practical problems with sulfide equilibria in numerous applications, S2−(aq) should be expunged from the chemical literature. Thermodynamic databases involving sulfide minerals also need careful revision.

Certainly the S2- ion exists in various forms and conditions but could it be that we are only now just learning that so many reaction mechanisms -as we understood them up 'till now- are erroneous? Would be nice to read the article in it's entirety... Hint ;)


Chemical Communication issue 16

aga - 20-3-2018 at 14:36

Meh.

S2- in aqueous could easily be an effect of S0, S-1, S-1.5, S-2, S-2.5, S-3 etc.

I.e. S transitioning between 0 and wherever.

Nothing is in a steady state, Ever, so all same-same.

DraconicAcid - 20-3-2018 at 15:43

Every first-year text I've seen lately (apart from the really old ones) states clearly that S(2-) is a strong base and doesn't exist in aqueous solutions, so this is hardly news.

mayko - 20-3-2018 at 15:54

Quote: Originally posted by Joeychemist  
Would be nice to read the article in it's entirety... Hint ;)


Chemical Communication issue 16


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byko3y - 21-3-2018 at 03:10

I needed like 5 minutes reading to understand what they wanted to declare a truth. The true ions can be described with a single formula from the paper:
HS- + OH- + Na+ <-> NaS- + H2O
So, basically, sulfide never loses its last cation in the presense of water.