Potassium to sodium equivalent.

Discussion in 'B&W: Film, Paper, Chemistry' started by Keith Tapscott., Sep 12, 2008.

  1. Keith Tapscott.

    Keith Tapscott. Member

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    What weight of potassium sulphite would be equivalent to 100 grams of sodium sulphite, anhydrous?
     
  2. Aurum

    Aurum Member

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    125.4 grammes

    Based on Molecular weight of K2SO3 being 158.26, and Na2SO3 being 126
     
  3. Keith Tapscott.

    Keith Tapscott. Member

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    Thanks, do you or anyone else know how much is soluable in a litre of water?
     
  4. Aurum

    Aurum Member

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    The Merck index says "Potassium Sulfite is soluble in 3.5 parts of water", Though doesn't say if thats the anhydrous or the hydrate.

    If you take that as Weight for weight,Thats a 28.5% solution . (or 285g/Litre)

    So I would say 250g / litre should go together OK (And keeps the sums easier if you're making a stock solution for using in other stuff)

    It also says that its Cathartic and Diuretic, so wash your hands afterwards before eating, unless you want to be fixing prints in the bathroom, sitting on a porcelain seat
     
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