it's really ironic how all day i can think of so many things to blog about but when i'm actually sitting in front of the computer, all my thoughts are gone... so now, i'll just start with what i did today... hopefully it'll lead me to remember what i wanted to blog about initially.
i started the boron calibration last friday and it was so demotivating!!! the procedure involved evaporating the standard solutions on a steam bath (which took about 4 hours for 100ml standard solution), refluxing the dried standard in a muffle furnace at 550 degrees celcius for 1 hour, adding acid to dissolve the residue, centrifuging the resultant solution, adding 2 drops of concentrated HCl and 10ml concentrated sulfuric acid, waiting for the solution to cool down, adding the carmine reagent (which was practically concentrated sulfuric acid with red carmine powder) and waiting for 45 minutes for full colour development before taking its absorbance reading on the spectrophotometer. (see how long the method is!!!) on thursday after i'd finished the phosphorus calibration, i tried reading the SOP (standard operation procedure) for the boron calibration and half way through the procedures, i came across this phrase "... and triturate with a rubber policeman to dissolve." at first i couldn't believe my eyes, i thought i was seeing something wrong... what do policemen have to do with calibration methods? so i asked the lab technicians and they too didn't know what it was about... in fact, everyone had a good laugh over it! jokes were flying about non-stop till work ended! even the chemist didn't know what the phrase meant and wrote it off as a typo error. before i went back, i asked my supervisor what it meant (while trying very hard to stiffle a giggle) and turns out, it wasn't a typo error and simply means agitating the solution by blowing bubbles using a dropper (rubber policeman is the term used for the black rubber bulb)... i felt so stupid after that...
anyway back to my story, it took me the whole day to prepare the standards until the centrifuging part and i had to continue on friday morning. the results were totally and utterly out of the expected range! it was a total failure. i had to do the whole thing again (my supervisor suggested not diluting the stock solution this time). so i did everything again and had to stay till 6.15p.m. (overtime) to finish the calibration. again the results were as bad as the previous time... i think my supervisor kinda guessed i was getting abit fed up, so he asked me to redo it on monday minus the drying and centrifuging steps. it worked! and i'm so happy it's finally done and over with... whew!
ok, i'm starting to nod off... i've lost my train of thoughts. so i'll end here. i guess i didn't get to recall what i wanted to blog about.
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