134. gah / dang: i screw up chem spa

i cant find any word to describe my awe in screwing up chem spa but "dang" or "gah".

but never im sure most of the class wouldn't get the correct observations anyway. i filtered a mixture and forgot to wash the residue with deionised water. so when i added barium nitrate, i got a white ppt instead of a colourless solution. thats a scam because the residue doesnt have anything to do with the conclusion.

and also i didn't test for the gas given off. i saw the passing tube or whatever you called that but i didn't see there's limewater, which was written as calcium hydroxide in the basket in front of me. that's a scam too cause they would label as limewater during practicals, and the sudden change would be disturbing and unnoticeable. but then i guessed it's carbonate anion because there is no pungent smell given off after effervesence.

but someone told me that the top of the paper wrote to deduce all ions present. and then the bottom of the page says to deduce the identity of the anion and the possible cations in the filtrate and asked for explanations. so after the spa i wondered if do we write all the ions or just for the filtrate.

im also not sure if i deduced the right cations because i did the conclusion in a hurry. anyway the main point is im so screwed for chem spa, and physics spa would probably not be that good either.

and mrs seck asked me to filter the mixture for her to see. so i took up the boiling tube and the stirring rod and decanted it for her to see. she still remembers that during a practical, i once poured the mixture into the filter funnel without the stirring rod, lol.

posted by datf @ 7/29/2008 07:26:00 pm