Well, I had my first ever chemistry laboratory exercise today, and it was HELL. HELL!!
Things got off to a bad start when I walked in and found that my lecturer for organic chemistry was also the main supervisor for the practical exercise. I couldn't really do justice to him here, suffice to say not only did he not offer any help, but marched up and down the room with marksman eyes, and terrorised my bench for the whole morning.
I never had any experience of practical chemistry before, having done the subject in one year at a cram college, and so when I walked in to do my thing this morning at 9am (Calibration of a pipette, and titration of oxalic acid with sodium hydroxide), I was clueless. The night before, I ironed a newly washed set of clothes, including my lab coat, and had a shave, hoping that if I looked well on the day, I would feel well, and therefore perform well. Who in God's name was I trying to kid? Among the problems encountered:
1) Out of all the pipette fillers that I managed to get my hands on, only one of them worked. The first, ooh, SEVEN that I tried all had something wrong with them, but because I hadn't used them before, I thought the fault lay with me. The problem was rectified approximately 90 minutes into the lab.
2) My titre results varied wildly, but NO-ONE explained to me that this is normal when using different indicators. Did you know that methyl orange and methyl red change colour at pH 4 or pH 5, but bromothymol blue changes at pH 7, and Phenolphthalein at pH 9? I'll bet you didn't, dear reader, but that fact is now burned into my brain for all eternity.
3) We broke for lunch at 12. When I came back at 1, it was pointed out to me in mid-titration by a lab technician that my burette was blocked. This explained the fact that only one drop issued from it every ten seconds or so, but once again I had known no better. At this time, almost everyone else had gone, having finished up during the first period.
Among the many acts of stupidity I committed during this time was:
a) While using two identical beakers, constantly forgetting which of the two contained water and which contained acid, thus having to pour them all down the sink and start again,
b) Spraying an electronic weighing scales with water from a high powered tap. Mercifully no-one saw me so I quickly covered my tracks, and if it transpires that the thing is broken, I shall be at the back whistling nervously. Apparently you're supposed to report accidents like this. Ha!
And the coup de grâce…
c) Topping up my burette with the acid, when it already contained the alkali.
Overall the process could be likened to childbirth, though against all odds I collected my data, and my analysis worked out pretty much the same as everyone else’s. The report has now been handed in, and I can breath again. At least the assistant was supportive, saying that I should be fine from here on in. I don’t care. All I know is that I don’t have another one for two glorious weeks.
Unfortunately, I have that nazi at 10am tomorrow morning for a lecture.
Science. Believe the hype, it is something to scream about.
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