For those of us who are a little "long in the tooth", you may remember Jean Michel Jarre and his synthesiser music from the 80s. Oxygene was one of those albums. Although oxygen was first discovered by Scheele in 1773, its discovery is usually attributed to Priestley who was first to publish his work in 1774.
The classical test for oxygen in the chemistry lab is to apply a glowing splint (a half-lit match) to a tube containing the gas. I came across a nice variation the other day and since it is such a long time since I last did this experiment, we video-taped it. A class of fourth year high school students from LSS Messedaglia, Verona, were investigating the kinetics of the KI catalysed decomposition of hydrogen peroxide in a variant of the "elephant toothpaste" experience, by measuring the height of the foam as a function of time. The foam traps the oxygen gas produced during the reaction which is a bit easier than fiddling around with gases in test-tubes or collecting them over water.
Update: today I repeated the experience with a class of students from IIS Calabrese - Levi (San Pietro, succursale). This video demonstrates the oxygen test very clearly...
Thanks to Marilena Righetti for suggesting this experiment in the first place.
A little after the event, here's a video from the workshop carried out at IIS Marconi in Cavarzere, VE, last winter. Even though the sound is not great, the video gives a taste of how the workshop panned out over the day. It was a long day for the students however, it was a great pleasure to work with them and they made a big effort along with their teacher Maristella (who put the video together).
Maristella presented this as part of a paper at the recent science teacher's conference in Padova in which she provided a different interpretation of the now familiar CLIL (Content Language and Integrated Learning) acronym:
Come Lavorare (di più) Insegnando (anche) L'Inglese.
(How to work more, teaching some English at the same time).
Well, we are nearly there. A few hours to go and we'll be on our way to Debrecen, Hungary together with the Italian delegation for the 2017 edition of the Science on Stage Festival.
Along with Francesca Butturini of the Angeli High School in Verona (Educandato agli Angeli, Verona), we are presenting "Rise and Shine - Chemistry at Breakfast Time" which is based on a series of laboratory experiences connecting traditional Italian and English breakfasts to the chemistry curriculum. We've got fermentation, eutectic mixtures, redox and extraction, which are all involved in some way in the preparation of the breakfast table.
Here are two videos from the project, placed here to make them easily available.
Something new for this summer!
Between the 12th and the 16th June we held a summer school entitled "Exploring Enzymes in English" at the Opificio Golinelli in Bologna. Wtih a small group of students we did some practical work on how to study the activity of enzymes from purely qualitative experiments with pineapple and gelatin, to quantitative measurements of cellobiase activity in mushrooms using a spectrophotometer.
The students seemed to enjoy the combination of activities; we tried to keep the theory to a minimum and even managed to have a look at protein and enzyme structures using the Avogadro and Rasmol programs in the IT lab.
I'd like to thank Raffaella Spagnuolo and the Golinelli Foundation for their support of the project, Thomas Zanello for his help in the lab and reflections on the activities and of course the students for their active participation and ability to create a team spirit considering that none of them knew each other prior to the summer school. This culminated in the video which the group produced as a record of the activities of the week.
Great job guys!
Van Leeuwenhoek did a lot with very little and if you look at the microscope that he used, you can have nothing but admiration for the patience that he must have had when observing and drawing what he saw. Microscopes are fairly commonplace these days, even in schools although they are expensive. They work by using a spherical lens to magnify objects up close with a second lens to magnify the image obtained.
Surpisingly (or not) smartphones can be combined with small short focus spherical lenses to create a very simple yet remarkably effective microscope. The spherical lenses used in laser pointers are ideal for this and with a few bits of perspex, wood, a drill and some bolts and the desire to play around a bit, it is possible to construct the phone-microscope.
I was really quite surprised by the quality of this very rudimentary array.
It's nearly that time again! The various Nobel prizes will be awarded sometime in the next month or so and as happens every year a little ahead of the official ceremony, we get the unofficial IgNobel prizes. A play on words and a chance for science to be seen in a more playful light.
There are a number of prizes in different categories (which don't necessarily correspond to the official ones), the point being to reward research which on the face of it makes little sense but which upon reflection can get people to think a little bit.
In the past we have seen a study reporting the brain scan of a dead fish, we have learned that chimpanzees can recognise each other from photographs of their bottoms and we have also encountered a patent application for a spray containing radish extract for use in waking up sleeping people in the event of emergencies.
Since the IgNobels publicise work which seems to be quite ridiculous, the press often distort the intention of the awards and forget that the scientists involved do real science. The content of the IgNobel research is typically only a sideline or as in the case of the brain-dead fish, is an illustration of statistical control for a far more serious application. This last bit isn't as newsworthy as "silly scientists wasting public money", because statistical control is not exciting news.
This year's prizes are described along with those of previous years on the improbable research website organised by Marc Abrahams. Check it out and find out what tastes like chicken!