Monday, 14 February 2011

The Woes of Demonstrating

I’ve had a day of demonstrating today. While this does put a bit of extra cash in my pocket at the end of the month, it is one of the more thankless tasks I have ever had the pleasure of doing.
I’ve posted previously on the sheer stupidity exhibited by these chemists of tomorrow, but I don’t recall a time when I was an undergraduate when I went out of my way to make the life of the demonstrators in the teaching labs really difficult. First things first this morning was a bromination of aniline. Dissolve bromine in acetic acid, and slowly add to a solution of aniline in acetic acid at 0 oC until the bromine colour persists. Easy right? Wrong. Having watched people carrying fairly large quantities of bromine around in the lab in open flasks, I could practically feel myself brominating. A few less than kind words to certain individuals may or may not have made me the flavour of the month, but at least I knew I wasn’t going to end up in hospital.

Following a barrage of stupid questions (Why isn’t my solution boiling? What colour is my reaction meant to go? Does my non-halogenated, organic waste go in the non-halogenated organic waste bottle?) and equally ridiculous actions (turning up the tap connected to the reflux condenser as high as it will go then proceeding to attempt to put a reaction on in what can only be described as monsoon-like conditions) to back them up, I gulped down a substandard baguette and a coffee at lunch before returning to more of the same. I for one didn’t realise that a recrystallization was a difficult concept to grasp once it has been explained once or twice but apparently I am in the small minority here. I watched today in disbelief as time after time people dissolved their product in huge amounts of ethanol and then wondered why lovely white crystals were not forthcoming. I gave up in the end and just watched them struggle for a while. My understanding, helpful side had literally been bludgeoned out of me and been replaced with my cynical, sarcastic one. The final straw that broke the camel’s back was being informed that someone “had no crystals, innit?” which was rasped at me in such a way that the assumption was that it was clearly my fault that a 5 gram reaction had produced 20 mg of amorphous crap. Having resisted the urge to throw myself out of the window at that point, I calmly pointed out that the activated charcoal they had used now consisted of approximately 80% pure crystalline 2,4,6-tribromobenzene and that a quick recrystallization would result in a much higher yield. He looked at me as though I’d just urinated on his shoes, threw his little bag of crud in the box and walked out. I can only hope I am marking his script, that’s all I’m going to say.

A two hour French lesson following my day of demonstrating was not high on my list of things I wanted to do. However, I persevered and am now a minute step closer to understanding that bizarre language they speak across the Channel. I sit here now, with something to eat and listening to some Elliott Smith, ranting about my day and it is definitely having the desired therapeutic effect. I hope everyone who has the (mis)fortune to stumble upon this enjoys reading about my day half as much as I did not enjoy taking part in it :P

Until next time, thanks for reading as always.


  1. Demonstrator plus

    18 year old ass. (First years are upsettingly tidy here- why couldn't rdg have had a similar proportion?)

    No columns for an hour and I can put off titrating that grotty old n-BuLi for another week.

    A tenner an hour.

    Demonstrating minus

    What does aqueous solution mean? (add water)

    Why isn't my steam bath working? (put water in it)

    Why dont I have crystals? (you've used ethyl acetate instead of water)

    Some suprisingly hydrophobic undergrads here.

  2. In my first year when my research was dead in the water, demonstrating was enjoyable. I was actually doing something useful. These days it's just an interference. Thankfully physical chemistry is low on practical concerns but there are three phrases that are now drummed into my psyche. "Did you read the instructions?", "Why aren't you wearing goggles?" and "LOOK AT THE EQUATION!".

    One of my friends, who is organic-y, had to deal with first years. One of them couldn't light a bunsen and went over to get him, waiting five or so minutes, without first switching off the gas tap. Sometimes you just have to despair.

  3. You get some points for listening to good music though Elliott Smith is likely to only make you even more depressed.

    With freshmen labs you have to be very patient and expect that some people in your lab are sloppy/unmotivated/retarded. You have to be extra cautious when people under your command work with bromine because bromine on skin promptly causes burns that are every bit as nasty as those caused by mustard gas - they are excruciatingly painful and take forever to heal.

    It does not help to fly into rage. Explain things patiently as if you were talking to a bright six-year old, without condescending tone, but with the necessary detail. Don't be a dick, try to talk to people in a pleasant way that does not insult them, but if someone persistently does stupid dangerous things in the lab, just ask him to leave and come again some other day.

  4. Elliott Smith was about all I could handle by that point in the evening!

    I think this post may have put me in the wrong light. I would like to think I am patient, helpful and understanding about 95% of the time and that I am actually a pretty decent demonstrator. I know exactly what it is like to wash an afternoon's work down the drain or drop it all over the bench so I know what they're going through when it goes wrong but it's just that odd time (like on Monday) when I'm really not in a great mood that a select few of them begin to grate on me.

    I'll have to remember your tips though. Talking to people about chemistry like I would a six-year old sounds like it could work!

  5. I have had some of the worst groups of students in my demonstrating days. One that sticks out in my mind was a lab on cross-linking polymers. Not a hugely difficult experiment; one simply takes a bunch of thermoplasts and thermosets, heat them, bend them, see how they behave and decide which they are from a list. To be fair to the students, they had not finished this lecture of material, so to make the whole scenario easier on both them and myself, I simply wrote the answer on the whiteboard and then told the class that this was the correct answer. All they had to do was copy it down word for word, and they would get full marks.

    When marked, only 20-30% of the class got this last question correct.

    The average (median) class mark was 4.5 out of 20.