As part of the Science festival, I took K, L and A to the Chemistry department. There was an unexpected bit of learning on the walk from the nearest free car park to the department – the very nice playground we went through had a Moebius strip climbing frame. I’m not surpised, given where it was, but it did make me smile and K and L had fun clambering over it.
I have memories of the Chemistry department from when I was a student – 3 9 o’clock Maths lectures there a week in my first year (because it had a large lecture theatre). When you got to the building, getting in was tricky because all the fume cupboards inside were sucking air out of the building and pumping it out of chimneys, which meant that the entrance doors were being sucked shut. My lecturer was Dr. De’Ath (convenient apostrophe), who was an astronomer, and the only thing I actually remember of his lectures was vector area. He held up an inflatable zebra and asked “What’s the vector area of this?” The answer was 0, as it is a closed surface.
Anyway, back to the present. The doors weren’t being sucked shut as the fume cupboards were off. There was a huge scrum in the entrance hall as lots of people were just about to go into a lecture. A quick hello to a local HE family who were about to go in, then we headed off randomly upstairs. The first room we came to had some nice crystal stuff – examples about the size of a rubic’s cube, and some kits for growing salt crystals with some here’s-some-I-prepared-earlier showing how they would work.
The best bit in that room was the liquid nitrogen. As well as the put something in, freeze it, take it out and smash it with a hammer trick (which was done with bananas, apples and an egg) there were two things I’d not seen before with liquid nitrogen. The first was making a chunky nail out of blu tac and then being able to hammer it into a plank of wood. The second was a foam trough that was having a blown up balloon pushed into it. The demonstrator asked us how many balloons we thought were in the trough. She then got some tongs and kept on pulling out more and more balloons. Most of them had gone down to as small as when they weren’t inflated, because all the air inside had shrunk down in the cold. The trough was about the size of 4 adult shoe boxes in 2 rows of 2, and there were 31 balloons in it. She put them on the bench where they warmed up and got back to normal size – the bench was covered with balloons, and it was a very impressive demonstration.
Next was a bit of Chemistry lego i.e. playing with Molymod. K and L made carbon dioxide. There were diagrams of common interesting molecules, and K asked me to make ibuprofen which while not being e.g. DNA is about 10 times as complex as CO2. The students demonstrating had helpfully made some building blocks (though none I could use) and K put the hydrogens on a ring to make benzene. The student said a bit about it (gives you cancer, good at dissolving things) and K said “The man had a dream about snakes eating each other and worked out its structure” – student was impressed and I had a PDM. They do remember some things I tell them 🙂 .
Next door was another student with different bowls to smell. Which was the odd one out? Caraway, dill, rose petals, orange and spearmint. I can’t remember which one it was (but I think they both got it) nor can I remember which chemical was involved, but it was about chirality – four of them had one version of the smelly chemical and the other had its mirror image. That was interesting timing, as that week scientists had worked out the chemistry involved in Thalidomide harming the body. I mentioned that to the student, and he said that even if you could produce a pure sample of the good Thalidomide, your body would turn some of it into the bad Thalidomide anyway. Hmmm…
We then went to a bit where the children could do experiments. There was a lab given over to getting ready – racks of lab coats, boxes of disposable gloves, and boxes of safety specs. I had A on my back and surprisngly they had no baby-wearing lab coats, so we settled for My First Safety Specs for A and caution for me. K and L had the full works – see Flickr.
The experiments were making snot / goo (borax, PVA and colouring), cornflour and water and an excellent demonstration of density. There were beakers with sugar solutions of different strengths, ranging from just water to a saturated solution. The different strengths were coloured differently, and by carefully slurping some up in a pipette and putting it out into a test tube (in the right order) you could make a rainbow.
We were starting to flag a bit, so we headed up to the top floor where there was more liquid nitrogen, but this time to make ice cream 🙂 . K and L were a bit too young to do it themselves, so they watched as a kind student made some for them and then gave us all some. Very nice it was too – very small ice crystals so not hard and crunchy, proper ingredients including cocoa and cream.
As we were going round we’d been doing a trail where you had to find posters about mystery elements. This certainly tested my rusty A level chemistry, but we got through it and collected the prizes just before chucking out time.
As for the title – my dad’s a physicist and was therefore indoctrinated with the view that chemists are just cooks in lab coats.