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  1. #41
    Photo Engineer's Avatar
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    Kodalk is listed as the Sodium salt of Boric acid and also as Sodium Metaborate Octahydrate CAS#.035585-58-1. So, it can be made on a molar basis by taking plain boric acid and adding Sodium Hydroxide to it until you reach the pH that you wish.

    That will do the trick.

    PE

  2. #42
    Ian Grant's Avatar
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    It's best to use Kodak's own recommendation of Borax and Hydroxide which they've published many times over the years in various Professional Handbooks.

    They clearly show that 10g Sodium Mertaborate (Kodalk) can be replaced by 7g Borax and 1.5g Sodium Hydroxide, and for DK20, DK50. DK60, DK93 etc.

    Ian

  3. #43

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    found some interesting:
    * borax with sodium carbonate react only at high temperature (~800-900C)
    * boric acid react with carbonate and produce borax:
    4H3BO3 + Na2CO3 + 4H2O = Na2B4O7+10H2O + CO2
    * reaction between calcium metaborate and sodium carbonate produce sodium metaborate
    Ca(BO2)2 + Na2CO3 = 2NaBO2 + CaCO3
    Last edited by Relayer; 07-31-2012 at 07:34 AM. Click to view previous post history.

  4. #44
    BradS's Avatar
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    Quote Originally Posted by sharperstill View Post
    You're NOT a chemistry person? Fooled me.

    Jon
    no...I'm definitely not a chemistry person. My sum total of formal education in chemistry amounts to one year of High school chemistry, one year of general chemistry in college and some independent study of a couple of text books in Organic Chemistry.

    I am a math person....ten years of grad school in Math & Statistics and a few more during undergrad.

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