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  1. #41
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    To be clear on this, pH has no real meaning in pure organic liquids and so any measurement is ambiguous. pH is the measure of H2O in equilibrium with H+ and OH- and you can see that in pure solvent all three of these can be totally absent and so you are measuring the electron excess or absence rather than the equilibrium.

    As you add water, the HOH (water) begin to disassociate and register true pH, but it is still interfered with due to the huge amount of organic solvent present.

    That said, all I can suggest is for you to try the experiment as the results could go either way. Intuition would say the pH would go down as you add water due to dilution, but equilibrium effects may force the pH to move up.

    The presence of DEA will affect this to some extent, moving it upwards.

    PE

  2. #42

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    If you think the synthetic rubber stuff on the eyedropper to be a decent oxygen barrier, you are totally mistaken. Don't trust anything other than glass, PET or metal to be a useful oxygen barrier at all.

  3. #43

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    Incidental presence of DEA by 15% volume of TEA makes significant increase in the activity of silver complex ions, even if the pH is adjusted to a predetermined target value by other means. This can mean faster development rate, more physical development, coarser or finer grain (depending on how the other factors affect) and so forth. Be careful. For research purpose, always use pure TEA, DEA, etc., so that you know exactly what you are using.

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