From: Katharine Thayer (kthayer@pacifier.com)
Date: 05/20/01-10:27:58 AM Z
Judy Seigel wrote:
>
. But if my serial surmises that,
>
>
> b. the *reduction* which "oxidizes" the gum is caused by UV light, and,
>
> c. the reason the still-yellow-orange dichromate remaining was not reduced
> was because it was protected from the UV light by the dark part of the
> negative,
>
> are correct,
While your (b) surmise is correct, your (c) surmise is not. Even where
the dichromate has been exposed to so much light as to produce a
chromium stain, there is still a great lot of unareacted, hexavalent
dichromate left.
kt
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