He didn't even notice!

I think Senior tech has lost her final marble, aided and abetted by Evil Tech no doubt, as this what I found at work today.

I think Mr M must be of the same opinion, as he was clearly too scared to mention anything when he came in eariler. Either that or he thinks it's standard practice to have a giant cardboard robot in the corner of the prep room! Surely it's not possible he didn't notice, especially since he had to lean round it to get a paper towel out the dispenser. However, scientific stuides have shown that people tend to only see what they expect to, like in the 'Invisible Gorrila' test, so I guess anything's possible. It would certainly explain why so many teachers fail to notice me hanging around and getting all their practicals ready. Maybe I'll write my own thesis on this strange phenomenon - the 'Invisible Sloth' test.

Hello, Goodbye

As Septembers go, this one has been manic. With new teachers in need of training, new labs in need of running, Evil technician on the loose, and 'Gauzegate', I haven't had a moment to catch my breath - let along any swing time! But at last, for five minutes, things seemed to have quietened down a bit (and it's Evil Tech's half day) so here I am - keeping you abreast of what's going down in the prep room while having a nice cup of well-earned tea, and a bakewell slice.


So, what's new this year? Two new labs, as already mentioned, which stretches are already thin (figuratively 'thin' at least, Senior Tech has actually put on a few pounds over the holidays by the looks of it) technical team even further. I've tried to convince HOD that we need another sloth if he hopes to get anything done properly in the science department this year, but he's simply been too busy messing up his new office to realise quite how much I do around here.



And we have those new teachers too. But of course new teachers also mean losing old teachers. Not always a bad thing in my opinion, as some of them can be a complete liability (here's wishing Mr 'innocent' K all the best in his new school!). And sadly we said goodbye to Mrs B too, but at least now you can suffer those hangovers delicate days in peaceful retirement. We won't forget either of you, or that party, any time soon. All we hope is that Mr A and Mr J are half the teachers you were, in both brilliance and idiocy.





Science Department Farewell Bash 2018



Right, well, no rest for the wicked, or the sloths it seems. Now, where did I leave that soldering iron...?

Sloths aren't dense...

... but Senile and Evil Technician definitely are. But are they more dense than water? or oil? or milk? If Evil Technician tried to drown me in honey, would I float? And does the ethanol Senile Technician adds to her tea stay at the top of the cup? So may questions that science can answer, and so little time.


And time is what you need to make a density tower. It took me a good part of a hour to carefully add the different layers of liquids so they would sit nicely on top of one another. But it looks so cool it was worth it. The liquids I've used are (from bottom to top): honey, UHT milk (stolen from the staff room), washing-up liquid, water (dyed red), vegetable oil, paraffin oil, ethanol (dyed blue).

I was about to try putting the different objects to see where they float/sink, but Evil Technician suggested we put me in! and I'm now hiding in the chemical cupboard until she gives up looking for me... 
...hang on a minute, it sounds as though the coast is clear - wish me luck.

Thermometer fix

Crikey, this heat is unbearable! And Evil Technician and I have been doing just he job to tip those pesky teachers right over the edge - fixing our thermometers. After all, they'd need to use them to measure the soaring temperatures of their labs, so we have to get rid of all those spilt alcohol bubbles, don't we?


And the best way we're discovered of doing this is tapping the part where the split is, repeatedly on the edge of a desk. (Preferably wood, and preferably when someone is trying to teach next door!) This banging vaporizes the alcohol and then it can move freely down to join the bottom reservoir where it belongs. It takes a while and the alcohol bubbles regularly form again halfway down, but keep banging and I promise you they will eventually fall (sending you and your colleagues gradually mad in the process.)

Happy tapping!

Safety first

At last, I got my own pair of safety specs. I've been on at Senile Technician for months that I needed some proper PPE, but she's got a memory like a sieve (and a very lax attitude to health and Safety in my opinion). Hopefully I'll get my custom made lab coat soon too, then we'll be in business.

Aren't I adorable!

Self Sabotaging Universal Indicator

UI colour chart

I caught Evil Technician pondering how to sabotage a simple pH experiment today. She had test tubes of sodium hydroxide solution (NaOH) mixed with universal indicator solution (UI), which showed the students sodium hydroxide was very alkaline - a strong purple colour. However, as she pondered (and this took a while as Evil Technician can be a bit ditzy sometimes), the experiment seemed to sabotage itself - the UI and NaOH mixture turned blue!


Pleased with that result she carried on with her day as usual, but I just had to know why. It just didn't make sense. NaOH is one of the strongest alkalis we have in the lab, how did it go from pH 14+ to ph 9?


I tested the NaOH/UI mixture with UI paper, just to check, and it told me it was still pH14. Which could only mean the UI solution was changing colour by itself - weird, eh?


Admittedly, it took me a good part of a afternoon to discover its secrets, but I managed to convince Senile Technician it was important scientific research so I think I've got away it. Here's what I found.

Universal indicator is in fact made of four other indictors mixed together!!! Who knew? (clearly James Kennedy did as I got this poster from his website). But why would this mean it changes colour in NaOH?


The answer lies in phenolphthalein, an indicator which is colourless in acid but turns bright pink in alkali. At least, it does for a while. In NaOH solutions of pH 10 and above, the pink colour fades over time. There is a very confusing essay on the kinetics of it, but here's the gist - phenolphthalein is magic.


So with this magic, given time in NaOH, the purple end of UI spectrum disappears, giving the impression NaOH is less alkali then it really is.


Uh-oh, Evil Technician's come back and she's grassed me up. I really have to get back and do some proper work anyway or no classes will get any practicals that work this week. Honestly, I have to do every thing round here.

Evil Techincian changes her ways?

I think Evil Technician is up to something. She said my fur looked nice yesterday, and she managed to fix that indigestion tablet practical so it actually works now - no more counting hundreds of drops of acid in an attempt to neutralize a peppermint Rennies -Yay! She's even let me share her method with you (don't worry I've checked it and it all looks good - see below). Anyway I can't see her good behaviour lasting mush longer though. She's already given Mr K universal indicator solution instead of iodine to stain his onion slides today. I doubt it was by accident.

Time will tell

I've had to remind Senile Technician, again, that we really need to start building our time machine soon, or that unexpected amylase we found in the fridge will never materialise.


You see, Senile Technician writes the delivery date on all the chemicals and stuff we buy, and a few years ago, when we all thought we couldn't do an enzyme experiment because we didn't have any in-date amylase, a small tub of the staff (labelled up June 2018) turned up in our fridge to save the day. Well, technically it didn't save the day as the experiment still didn't work, but enzyme experiments never work, do they?

The point is, this was indisputable evidence that this year we must build a time machine to send the amylase back to ourselves.

I've been reading up on the subject. Despite the fact I'm a sloth, I really enjoyed: How to Teach Relativity to you Dog, by Chad Ozel. And I  read Brian Cox's, Why does E=mc2, which was also good (although I'm considering writing to Professor Cox to suggest he changes the title to How to Teach Relativity to your Sloth). And finally I'm half way through Steven Hawkins, A Brief history of Time (the illustrated version), although reading this is just a formality as I'm convinced I can solve the problems of bending space, light speed and time cones with a couple of magnets, that dodgy Van-de-Graaff that needs fixing, and an old microscope box. All that I need to complete the design is a frogger, which at the moment I can't seem to find. I think Senile Technical has misfiled it somewhere (I doubt she even knows what it's for). I do hope Evil Technician hasn't thrown it out by mistake on purpose.

Thinking of Evil Technician, it has occurred to me that perhaps we don't build our time machine this year at all. Perhaps we build it years in the future, then Evil Technical finds some really old out-of-date amylase from the future fridge and sends that back instead. No wonder the enzyme experiment didn't work! She really is a menace.

Oscilloscoping

We had our annual Professional Development review this week. Senile and Evil Technicians both got highly commended for their folders by the Deputy Bursar! I don't know how they did it, everyone knows I'm the real driving force and science genius in the prep room.

I've had a look at their exemplar folders, and I suspect they have been fabricating evidence. And it looks as though our physics guru Mrs B has been helping them too. I mean, who has ever heard of 'Oscilloscoping'. And why wasn't I invited on this course? They probably just wanted to eat all the free biscuits themselves - greedy gits.

Not that I needed to attend, of course (although the tea and biscuits would have been nice). Whatever oscilloscoping is it can't be that hard if those two idiots can do it. Here are their notes on the subject of getting AC and DC waves on an oscilloscope. Looks simple enough.

TLC

Every sloth needs a little tender loving care once in a while, but unfortunately I'm not getting any here. Evil Technician is off somewhere wiring up faulty circuits and I think Senile Technician has fallen asleep halfway through dunking a digestive. I do have the other type of TLC here, though, as Mrs H is doing a practical with her Year 13 chemists today - Thin Layer Chromatography. I hope they are grateful, as its  thanks to me they can do it at all.


The trouble with TLC plates, is that here they are supposed to show the chromatograms of various pain killers under ultra violet light. However, the UV light we had in the department was the wrong wavelength (longwave) to make the dust on the TLC plates glow green, and even with the right type of UV light (shortwave - Timstar sells one that works for this) the pain killer spots are hard to see. And under normal light they just look plain boring.


So, after a little research, I discovered that you can use stains to develop the chromatograms instead. The best stain I found was Potassium Permanganate (made by adding 1.5g potassium permanganate, 10g of potassium carbonate, couple of drops of sodium hydroxide and 200ml of distilled water).


To get the chromatogram in the first place, all you do is crush up your painkillers with some ethanol, then using a capillary tube add tiny spots along a line 1cm from the bottom of the plate. Put this is a developing chamber (I used a jam jar with a lid) with 10ml of ethyl acetate in until the solvent reaches 1cm from the top of the plate. Then remove the plate and wait for it to dry.


Once its dry the fun can start. If you have a UV that works use it now to see the spots. Then dip your TLC plate into the potassium permanganate stain. It will come out pink, and perhaps a few brown or yellow spots might be already visible. But after some gentle heating in front of an electric heater or something, more dots will magically appear.

This is the one I did. From left to right the painkillers I used were paracetamol, ibruprofen, aspirin and Anadin extra (you can see from this Anadin extra has both paracetamol and aspirin in it). And the best thing about was - it looks so pretty (just like me, only more pink and less sloth-like). Sadly it doesn't last forever, as the pink stain goes brown and fades over time. (Luckily I'm already brown, and hang around much longer.)


Anyway, Mrs H is eternally grateful for all my hard work on her practicals. She said I could hang out in her lab anytime and she tickled my tummy for extra TLC. She really is my favourite teacher. And I'm sure I'm her favourite technician too - I've definitely never seen her tickle Senile or Evil technicians' tummies anyway!

Fruit Tea-gate!

The BBC has a lot to answer for! I almost fell off my branch when I heard their headline this morning – Fruit teas can wear away teeth!!

Now, being a sloth I don’t have many teeth to start with, but luckily mine continually grow and don’t have any enamel to erode either. However, Evil & Senile Techcnians sit around drinking fruit tea all day, so, never to take a dubious news article by its word, I decided to take matters into my own claws and investigate further.

It is the acid in drinks which destroys tooth enamel so I tested the pH of their teas throughout the day, using universal indicator paper. And, despite the BBCs claims, they were not all acidic. Here you can see my results. From left to right: Lemon & ginger - ph7 neutral, Raspberry & echinacea - pH 6, Blackcurrant & blueberry, Blueberry & apple - both acidic. I don't know who they get to test their drinks at the BBC but they clearly need a sloth on their team to either check their teas, or their choice of words. (The only times sloths use the word all in science is to say that all science is theoretical - feel free to correct me if this is wrong, English is a sloth's second language after all.)

They might also like to consider employing a sloth in their research department too, as, in reading BBC Newsround's report on the same subject, I have noticed another scientific error. At the end of their article they go on to list drinks which are not acidic. Here they have included sparkling water. Even I know the bubbles in sparkling water are made of carbon dioxide, and if you dissolve a non-metal oxide in water you get... yes, you've guessed it - an acidic solution.

So, it seems the other Technicians' teeth will be fine for a few years to come, although there is still a good chance they might just wear away with the gassing they've been doing lately. Don't they realise they have work to do!