Tuesday, March 24, 2009


Cliches are useful.  That's why they haven't kicked the bucket, bought the farm, or been buried six feet under.  And when it comes to the idea that "the devil is in the details," I understand what it means.  Sometimes the details wring tears out of your face like nothing else.  For example, in a paper I'm working on, I'd cited EPA maximum contaminant levels from one source, and thought I was done with it.  Oh, no, brother.  When I started converting the supposed "microgram per liter" values to molarity, I was coming up with picomolarlity-level limits.  WHAT?  I was expecting micromolarity limits!  Hmm... I doublechecked the source.  Looking at the EPA site directly, I found that the book had miscited the EPA: the actual values were in "milligrams per liter."  Well, whatcha know.
   Then, today, I was looking up the structure for iron(III)ammonium citrate.  Straightforward, right?  Ha, no.  I found it on Sigma-Aldrich and redrew it in ChemDraw.  To make sure I had it right, I checked the mass.  When I compared it to the one listed for the product, it was different by a good amount.  Whaa??  It turns out that I had faithfully copied their structure, BUT their structure didn't agree with their listed molecular weight!  Comparing their structure to ones from other websites showed that a fiesty carbon had inserted itself into Sigma's structure.  WHOOPS! 
    It's just stuff like that that makes you scratch your head (ha! gotta keep those cliches going!) and wonder what else you're missing!
    But on the bright side, it makes me happy that I didn't find it the day of my prelim when idly glancing through the pages of my report, or when a committee member does the math and figures out my egregious error.

No comments: