From: Rauch, Shelley (rauch@yorkcounty.gov)
Date: 04/01/03-02:35:37 PM Z
>>>HOWEVER, SHELLEY ! MIX UP YOUR CHEMICALS A DAY IN ADVANCE. NOBODY SEEMS
TO HAVE NOTICED MY ADVISORY THAT VERY FRESH CHEMICALS CAN WASH OFF OR
OTHERWISE BE GOOFY. I doubt you'd get a 2 hour exposure even at the north
pole if everything else is in order.
I purchased them at school, and then used them the very next day. I'm not sure how fresh they were.
>>>Are you using GREEN ferric ammonium citrate?
Hmm. We were never told what they were... just to mix up equal parts A & B.
>>>Did you say what paper you're using?
I'm using BFK (something follows after this, but I'm afraid I don't remember).
>>>And you're buying chemicals in such small amounts that 2 tests use them
up? From where?
We can purchase little brown bottles of the materials for $5.00 from the school. I actually coated 5 pieces of paper with it. Actually, when I say I ran out, that's not quite accurate. I ran entirely out of B, but A had about 1/4 of the chemical left.
I just purchased some more this afternoon, and won't be making my exposures until this weekend (please, no rain!!)
I told my teacher what had happened, and showed her the papers. Her answer: you underexposed them.
!!!
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