What is the process of peptization in chemistry

  1. I read on a website that by washing a precipitate with too much de-ionised water; the precipitate is Peptized and thus some precipitate is lost.

    I am having a hard time understanding what peptization is? Can somebody please help me understand in simple terms for an A level student?
     
  2. jcsd
  3. Borek

    Staff: Mentor

    Have you checked wikipedia?
     
  4. I didn't understand the wiki article tbh english isn't my first language and I was hoping if someone could explain it. In less technical terms?
     
  5. Borek

    Staff: Mentor

    You have a suspension of very fine, charged particles. They don't precipitate, because they repel each other. When you add an inert salt, its ions get attracted to these particles, neutralizing the charge. In turn precipitate can be formed, as the particles stop to repel each other. If you wash the precipitate with deionized water, you remove inert salt ions, precipitate particles become charged again and can dissolve.

    If it is still too technical, please explain where you get lost.
     
  6. Okay so can this also apply to Barium sulfate precipitate? If you wash the precipitate with about 1 bottle of De-ionised water will it be peptized and some of it lost??
     
  7. Borek

    Staff: Mentor

    No ,idea, but I have reasons to doubt. Barium sulfate is not colloidal. Then, washing it with deionised water is not the best idea for other reasons.
     
  8. What will some of those reasons be?
     
Know someone interested in this topic? Share this thead via email, Google+, Twitter, or Facebook

Have something to add?