13:00 Sep 26 

P34 Effect of a triclosan/PVM/MA copolymer/fluoride dentifrice on ... - [ Traduire cette page ]Bacterial formation of the volatile sulfur compounds hydrogen sulfide (H2S) and methylmercaptan (MM, CH3SH) within the .... combination of triclosan, a polyvinyl methyl ether maleic acid .... this N-oxidation reaction and the substrate load it has to process. ...... Results <150 ppb of Volatile Sulphidric Compounds ...
doi.wiley.com/10.1111/j.1601-0825.2005.01105_57.x


"Volatil compound" !!!

12:10 Sep 26 

Since the text concerns concrete deletion, the generation of H2S under discussion must be via bacterial corrosion - and hence generated in gaseous form ..eg see http://www.statemaster.com/encyclopedia/Concrete
"Bacteria themselves do not have noticeable effect on concrete. However, anaerobic bacteria (Thiobacillus) in untreated sewage tend to produce hydrogen sulfide, which is then oxidized by aerobic bacteria present in biofilm on the concrete surface above the water level to sulfuric acid which dissolves the carbonates in the cured cement and causes strength loss. Concrete floors lying on ground that contains pyrite are also at risk.."

09:45 Sep 26 

About CO2: I did not say "CO2 IS an acid", but "CAN BE". In other words, it can behave as an acid.
Just think about th blood pH whose acidity depends on CO2 level...
I'm sure you know about. There are tons of reference talking about.
But anyway, it's not the purpose here.

I also agree with the rest of your comment, very technical, that should also explain why to avoid certain sources of "non scientific" information (i.e. some dictionnaries) to deal with chemistry; a very complex problem.
It would be very usefull here indeed, to have more context for the translation, especially to understand if we are dealing with an aequous or a gas phase.
In case of "biochemistry" I would for sure go with H. sufphide; in case of chemical reaction I don't think so, or at least t would depend on the reaction phase to my modest opinion.

04:26 Sep 26 

Actually for the binary compounds of hydrogen we have some sort of a grey area in nomenclature.

Stricto sensu they should be named respecting the rule that the most electropositive element comes first. But that's a rule with lots of exceptions...
Then there are the rules for naming the acids, one of those being that to a ion whose name ends in "...ide" (e.g. chloride), the corresponding acid gets called "hydro...ic acid" (hydrochloric acid). And again the exceptions.

As Lionel_M observed, when we're dealing with the pure H2S, gaseous, it's often called "hydrogen sulphide"; but "sulphydric acid" is at least as common in chemical articles... and treated as "more correct" by many authors.

In this particular case, the problem of whether to call it "sulphydric acid" or "hydrogen sulphide" is a non-issue -- both are okay. For congruity with the Italian original, personally I'd go for the "acid" form.

And a side note, for a comment in the answer section: CO2 is NOT an acid. To put it simple, it's an oxide which in solution presents acid characteristics due to its reaction with the water, when the (instable) carbonic acid is formed (H2CO3).

12:59 Sep 25 

Correct Doc, H2S in gaz is almost always "hydrogen sulphide" (eggs profume...) while in solution we should (chemically) use sulphidric acid

12:57 Sep 25 

Sul`phy´dric definition
a. 1. (Chem.) Of, pertaining to, or designating, hydrogen sulphide, which is regarded as an acid, especially when in solution.
http://www.thefreedictionary.com/Sulphydric

translation you use therefore depends on the text - whether they are referring to h2s as a gas, or in solution

12:50 Sep 25 

dont know if this sheds more light on your previous question, but this reference says 'Reduction of elemental sulfur or thiosulfate results in production of hydrogen sulphide H2S.'

http://www.onepetro.org/mslib/servlet/onepetropreview?id=NAC...