The chemistry lab, until a few weeks ago, was my least favourite place to be in. How people could pipette out was a mystery to me and concentrated sulphuric acid was my sworn enemy(well, the thought of heating anything with it and passing the ghastly orangish red fumes evolved into another test tube containing something else still somewhat terrorises me). I was the butt of ridicule and harassment for being unable to pipette out. My first practical exam left nothing but a sour taste in the mouth with me being given a big lecture by a teacher about the importance of volumetric analysis in chemistry practicals. This was because I could not pipette out on the big day as well. They just blew it out of proportion that day. The authorities treated me as if I was not pipetting out on purpose. Just because of not being able to pipette out, it was assumed that I could not do anything in the chemistry lab. Everything in the chemistry lab seemed to be against me. The chemicals, the authorities, my class-mates, everything.
The second term arrived, but my anathema towards chemistry practicals remained. Well, how else do you expect it to be? The first practical session of the term had an excessive blast of concentrated sulphuric acid with us being required to perform the manganese dioxide test for the presence of bromine and iodine in a salt and the copper turnings test and the brown ring test for the presence of nitrate in a salt. Since we were performing the tests for the first time, we were provided with a bromide, an iodide and a nitrate so that we could see the desired results. I gasped on coming to know that all the tests involved concentrated H2SO4. But,I somehow escaped the MnO2 tests that day as I was able to complete only the copper turnings test and the brown ring test by the end of the practical session with my brown ring hardly taking shape. My teacher complained of not enough diluted sulphuric acid. Sigh. Well, I had not completely avoided the MnO2 tests, as my test for iodide was a failed attempt as I had added MnO2 in excess slightly. That drew another complaint from my teacher. Sigh again. After I returned to my desk, she announced that the session was over and I gleefully washed my test tube and hands, took off my lab coat and left the lab. However, the effect of the lab session still lingered due to Mr. Concentrated Sulphuric acid and the amazing smell that he gives off. We are instructed to drink water after every lab session, but despite doing that, my chest felt tight, my head throbbed and whatever smelt bad, smelt like conc. H2SO4. It took 2 periods after the lab session to come back to normalcy. I swore to never enter the chemistry lab without a handkerchief thereafter. First lab session of the second term, nothing different.
The Dusshera/Navaratari/Puja holidays and the holidays due to Cyclone Nilam came and went and the second practical session of the term arrived. Surprisingly, I left the lab that day with a smile on my face as I had, for the first time, been successful in whatever I did in the lab. The tests for acetate, sulphate and phosphate went on smoothly. Similarly, the next 2 lab sessions went on smoothly with sulphide, sulphite,oxalate, the basic radical tests(the golden spangles formed after performing the potassium iodide test for the presence of lead were wonderful to look at) and the practices that the lab people gave us to find out the unknown acid radical in a given salt. Salt analysis had never been much of a problem for me,but the fear receded and I grew in confidence. I mastered boiling distilled water with the given salt and sodium carbonate to prepare the sodium carbonate extract for wet tests. I also mastered heating solutions in a test tube. I grew to like Salt analysis, not fear it.
But, there was one thing that had yet to be conquered. Pipetting out. The words that haunted me in the 1st term. But, I was determined to set that one right as well as being able to pipette out is very crucial in volumetric analysis. The day my teacher taught redox titrations in class, I went home and told my mother that I had to practise pipetting out at home to set that problem right. So, my mother bought two pipettes and I practiced. I was able to pipette out the first time I did it at home and even had a few episodes of tap water going into my mouth. I practised and practised and finally grew in confidence. My mother assured me that despite the pipette at home being thicker than the pipette in school, I would be able to pipette out during the exam as it is easier to pull a liquid through a thinner medium than a thicker one. If I was able to pull it through the one at home, then I would definitely be able to do it during the exam. My mother also assured me that due to the in-built defense mechanism of humans, NaOH would not go into my mouth.
The day of the chemistry practical exam dawned(last Wednesday). I was thorough with all the salt analysis procedures and entered the lab in a good frame of mind. I took my seat, noted down the questions and began my volumetric analysis. The sight of NaOH racing up the pipette filled me with joy. The first time I did it, the colour of phenolphthalein did not disappear despite the reading on the burette going past 17(disappearance of the pink colour denotes the end point), so I washed the conical flask, refilled the burette and pipetted out again. This time, I ended up with a value of 19.1. I was very happy. Before entering the chemistry lab, I had told my teacher that I was able to pipette out. She was happy and asked me when she called me for my viva assessment how I practiced pipetting out. I told her how. The viva was not that good; I got 3 and a half, but a lot was learnt. The teacher had asked the same core experiment(study of shift in equilibrium) as she had asked before and I creamed it. I could not believe my eyes when a white precipitate was formed and a brisk effervescence was produced when I added diluted HCl to my salt. My salt was a carbonate; the radical which requires the easiest test to confirm its presence in a salt. The salt looked like baking soda and when I added dil. HCl, it was confirmed that the salt was a carbonate. I had avoided Mr. conc. H2SO4. Let him rest for a while. I am not that afraid to face him. I went home with the satisfaction of having had a great chemistry practical exam.
I am no longer afraid of the chemistry lab. I am happy that I have finally overcome this obstacle.
(Also posted on the blog "Pursuit of Boredom")
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