Sodium Sulfide Question

**C_Remington** · 23-Dec-2013, 13:12

So I bought some of this from Photo Formulary awhile ago. It doesn't indicate whether this is anydrous, monohydrate, etc.

If not labeled, what is the customary default assumption??

thanx

**Jim C.** · 23-Dec-2013, 13:22

I've always taken anhydrous as being dry, like a powder, crystals or pellets.

**C_Remington** · 23-Dec-2013, 13:47

Well, all dry chemicals can be in the form of power, crystals or pellets. The anydrous, etc. nomenclature refers to the molecular structure. Specifically, how many water molecules are present.

It will make a difference when you go to weigh them out.

**Richard Wasserman** · 23-Dec-2013, 13:50

Sulfide or Sulfite? How about asking Photographer's Formulary directly? I'm sure they'd be happy to answer any questions you might have about their products. http://stores.photoformulary.com/-st...cator/Page.bok

**C_Remington** · 23-Dec-2013, 14:19

Sulfide. I actually thought this would be easier. I guess I"ll try there next.

**Cor** · 24-Dec-2013, 04:03

If it's used for a toner it does not matter too much, you usually tone by inspection, see also:

Sodium sulfide
From Wikipedia, the free encyclopedia

Sodium sulfide is the chemical compound with the formula Na2S, or more commonly its hydrate Na2S·9H2O. Both are colorless water-soluble salts that give strongly alkaline solutions. When exposed to moist air, Na2S and its hydrates emit hydrogen sulfide, which smells like rotten eggs. Some commercial samples are specified as Na2S·xH2O, where a weight percentage of Na2S is specified. Commonly available grades have around 60% Na2S by weight, which means that x is around 3. Such technical grades of sodium sulfide have a yellow appearance owing to the presence of polysulfides. These grades of sodium sulfide are marketed as 'sodium sulfide flakes'. Although the solid is yellow, solutions of it are colorless.