chemical question

Discussion in 'B&W: Film, Paper, Chemistry' started by glbeas, May 31, 2005.

  1. glbeas

    glbeas Member

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    What is the difference between the bisulfite and the metabisulfite, if any?
     
  2. john_s

    john_s Subscriber

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  3. glbeas

    glbeas Member

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    Thanks! Quite interesting how that works out.
     
  4. dancqu

    dancqu Member

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    Likely one difference is the temperature of crystallization; the
    meta being precipitated at higher temperatures. A dehydration
    takes place. A combining of two orthos into one meta minus one
    H2O is the result. The metabisulfite is two bisulfites minus a H2O.
    Or, 2,NaHSO3 = Na2S2O5 + H2O.

    Borates do the same thing, dehydrate; ortho, meta, tetra. Of
    course they also hydrate; metabisulfite, with water, will become
    the bisulfite. Dan