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Archive for October, 2010

Ramon Llull portrait

Portrait of Ramon Llull

As we have studied the history of chemistry for our recent unit in Honors Chemistry, I’ve had my students do a bit of research on what is known and supposed about various alchemists. For example, a student in each of my sections was assigned to research Ramon Llull, the Majorcan alchemist. We started by finding out what is known about the real person. He was born in Palma in 1232 AD, and was a courtier, poet, and womanizer at the court of King James of Aragon, then had a religious epiphany that converted him into a fervent missionary for Catholicism. After a nine-year hermitage and writing many religious tracts, he set off on a series of missionary journeys to North Africa. He was fluent in Arabic and was unusual for his time in that he believed in converting the Muslims through reasoned argument instead of Crusades and the sword. He wrote some of the first works in Catalan, his native language, and died after being stoned in Tunis.

Ramon Llull title page

Ramon Llull title pagae

I also had the students research what is attributed or credited to the person in tradition and later writings, such as Ramon Llull’s alchemical works and his having created the Philosopher’s Stone.

Uroboros from Michael Maier

Uroboros from Atalanta Fugiens

Each student also had to find an image of the person and include it, then take their short report and convert it to simple bullet points to summarize their findings. I’ve now taken those bullet points and turned them into a Keynote/Powerpoint slide show and added their images as well as photos I took last year at the Chemical Heritage Foundation as part of my fellowship sponsored by the Société de Chimie Industrielle (American Section). This is the first time, except for a few progress report blog posts, where I have started to use all the materials I assembled. I am attaching it here, and hope you enjoy going through it and using it in your own classes.

Alchemy_History (Powerpoint)

Alchemy_History (PDF)

Sorcerers Apprentice

A Sorcerer’s Apprentice Masters the Transmutation of Copper into Gold

It was my privilege last summer to dig into the very books these alchemists wrote, and I’m still digesting what I discovered. One result has been my own creation of the White and Red Elixirs and the formation of the Stone itself; in fact, I demonstrated my alchemical prowess for my students by converting copper into silver and then into gold. Several of my students had achieved the inner transmutation sufficiently to successfully direct the Stone’s powers as well, as shown in the photo. (Of course, we really aren’t making gold. This is the old “Alchemists Dream” activity where copper pennies are coated with sodium zincate [using a combination of 6.0 M sodium hydroxide and zinc powder], then heated gently in a Bunsen burner flame to alloy the zinc with the copper to form brass, which looks like gold).

Basil Valentine

Portrait of Basil Valentine

These student-created projects are part of my overall philosophy of science education and the main rational of this Elements Unearthed project: that students learn best when they are actively involved in sharing their knowledge with others. With modern tools for publishing on the Internet through blogs and PDF files, Powerpoints and videos, students now have an audience for their work that is much greater than simply their peers and teachers in class. Tomorrow is the unit test; we’ll see if my theory holds water then!

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by Eli West

Guest Host

Thorium reactor

Liquid Thorium Reactor

The word “nuclear” means a lot to us today. When we hear it we think of many things: bombs, reactors, uranium, “nuculur,” and radioactive; all of these are connotations of the word nuclear. Let’s explain what each of them means.

We’ll begin with bombs. The common link between nuclear and bombs, is obviously, nuclear bombs; otherwise known as atom bombs. In essence, you have a collection of uranium atoms; specifically Uranium-235, which is very fissile.  In a bomb, a lone neutron is shot at a uranium-235 atom to create uranium-236. Since uranium-236 is too unstable, the isotope breaks apart very violently, shooting neutrons everywhere, and these reactionary neutrons in turn smash into other uranium-235 atoms, and those atoms break apart and smash OTHER atoms. Which is what makes atomic bombs so explosive.

Another think we link to nuclear is uranium. Uranium is a very heavy atom. With a standard atomic weight of 238.03 g/mole, it’s on the heavy side. However, you’re probably used to hearing terms like uranium-238 or uranium-235. What do the numbers mean? Why are they different? What does it change? The number with uranium is indicating the isotope number, which simply means that there are more or less neutrons with the same number of protons. The 238 number gives you the atomic weight of the atom. In order to find out how many neutrons there are, you simply take the atomic number (which is 92, the number of protons in all uranium atoms, regardless of isotope), then take the atomic weight minus the atomic number to find the number of neutrons. In this case it is 238-92=146. So we know that there are 146 neutrons in each atom of uranium 238. Compared to hydrogen, that’s heavy.

Nuculur. I’m not even going to go into that, except to say that the correct pronunciation, by the way, is “new-clear.”

Radioactivity: it’s a word with a history. It’s a word that’s gotten a pretty bad rep over the years, through romanticizing, myths, and fiction. Everyone has heard the stories of people getting hit with gamma radiation and gaining super powers! Or of radiation being like the Black Death, destroying any who get near. The truth is, EVERYTHING is radioactive. Now don’t get scared! That term isn’t quite as bad as believed! Let’s get a few things straight, what exactly does, radiation mean? Well, everything radiates. EVERYTHING. Radiation is just the constant output of energy. We radiate heat, and light, just like the sun; food radiates heat! Some things just radiate such high-energy waves that they become dangerous. THAT is radioactivity.

“Radioactivity refers to the particles which are emitted from nuclei as a result of nuclear instability.”

http://hyperphysics.phy-astr.gsu.edu/hbase/nuclear/radact.html

Thorium in USA

Thorium concentrations in the USA

Now, where I am going with all this is thorium. What is thorium? It’s an incredibly heavy atom, much like uranium. It has large isotopes, much like uranium. Both of them have a huge half-life, and are highly radioactive; the differences between them are: (1) uranium, when used in nuclear reactors, produces a new isotope of uranium, which can be weaponized in the form of depleted uranium. It can be formed into what are essentially large bullets crafted out of the depleted uranium isotope. The bullet is incredibly dense, and when shot at high enough velocities, can pierce tank armor. It doesn’t explode in a nuclear bomb, but it does spray radioactive uranium all over the inside of the target tank. Thorium, on the other hand, when used in a nuclear reaction will not produce a weaponizable material. Thorium and uranium are both naturally occurring materials.

Thorium is abundant compared to uranium. So as a fuel source it would be cheaper, MUCH cheaper. Thorium is not fissile itself, which means it cannot sustain a low energy chain nuclear reaction, which means that it is not actually usable in nuclear reactors by itself. However, it is fertile, which means slow neutrons can be added to it to change it into U-233 (or uranium-233), which is fissile. That’s why we can’t just start mining thorium and tossing it in nuclear reactors all over the world. First we need to create reactors that can change it into U-233, which would then be fissile.

Thorium deposits in Alaska

Thorium deposits in Alaska

The word thorium has a very simple background. The man who discovered thorium simply decided that Thor was a pretty cool guy, and that maybe he should call this thing thorium!

As of right now there are a few companies around the world that are developing thorium reactors. Their projections for finishing the project are around 2015. That’s five years. Not to mention the actual two or three years it would take to build each reactor. So, the technology is coming, but is a ways off. Some believe that once they get the reactors running, that we could wean the world off oil in as little as five years, or by 2020. However, that’s probably a bit optimistic, and there still is a lot of work before we reach that point.

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The Five Elements

The Five Elements

As I teach chemistry and astronomy again for the first time in several years, I’m having a lot of fun getting back into the physical sciences with all of the lab experiences I’d collected and developed over the years before I started teaching multimedia exclusively. I’ve also added a number of excellent activities that I picked up from my experiences with NASA and from various conferences and presentations. It’s also a lot of fun to start incorporating my expertise in media design and technology in ways I never could before, as well as the materials I collected at Chemical Heritage Foundation in 2009. For example, I just finished teaching a Keynote presentation on Greek matter theories that I put together myself using photos, drawings, illustrations, and 3D animations (mostly my own) and information collected at CHF. I have all the files stored on various hard drives that all hook into my Mac Powerbook (about four terabytes total). Some of the images I pulled off the Internet at school using our wireless router and Airport technology, and once the Keynote was finished, all I had to do was hook my laptop up to a projector and give the presentation (complete with animations and audio clips) using an infrared remote. Here’s the presentation, in Powerpoint format. If you want to use it, be my guest:

Greek_Matter_Theories

To me, all of this seems remarkable, even miraculous. And here I am writing about it on a Blog, publishing my experiences instantaneously where anyone in the world can read them, and even sharing the presentation itself. Yet I feel as if I’m only just scratching the surface of what these new technologies can do. That’s part of why I’ve been working on this Elements Unearthed project for the past several years; there are so many connections between science practitioners and students that can still be made and which I hope to develop, so many innovative methods of teaching that no one’s thought of yet. I’m a digital immigrant; my students are natives. I’m always playing catch up to what they’re already using daily.

Engraving of Democritus

Engraving of Democritus

So far this blog has been written entirely by me (David Black) since it debuted in Oct., 2008. Now that I’m teaching chemistry again I am turning over much of the posting to my students, who will be taking turns once per week adding information about the research project they are pursuing. They have chosen between an element (such as copper), a material (such as cement), a method of generating energy (such as solar power), or a time period from the history of chemistry (such as medieval European alchemy) and are compiling notes into an MS Word document with references.

With each post, they are to include about 500-800 words of writing in their own words culled from all of their research notes and include relevant images or diagrams. They are also producing a nicely laid out document such as a newsletter, poster, or brochure that will be converted to PDF format and linked to this blog for download. It may take a week or two for the first few student posts to contain these linked files, but they will come. My hope is that any chemistry teachers or students out there who are reading this blog will be able to download these linked files and use them in your own classrooms.

Plato and Aristotle

Plato and Aristotle, Detail from The School of Athens by Raphael

During second term, the students will be developing and practicing a hands-on demonstration that involves some property or aspect of their topic. We’ll present these demonstrations to the elementary classes at Walden (I’ve already met with the teachers to plan this out) and the students will also present them to each other for feedback. During third term, we’ll create a more extensive project from their topic: a detailed Powerpoint or Keynote presentation or a three-minute video or a computer game. They’ll present these in class again, then fourth term put all of this together for a back-to-school science night for the public and their parents and siblings. We’ll videotape these presentations and share them with you as well.

I’ve done all of these things before in various multimedia or chemistry classes, but this is the first time that technology and opportunity have combined to allow me to put it all together. I am still looking to build partnerships with local organizations (museums, mining associations, etc.) that will combine my students’ media skills with their content. I’ll still visit mining towns, take tours of museums, and continue to post about how technology can be used in the science classroom. I also plan on writing more grants and professional articles. I’ll continue to create longer format videos to go with the student short videos (the Tintic Mining District is up next after I make some changes to the beryllium videos).

This blog has certainly been successful in what I’ve intended it to be. Last month (September) was the best month so far with over 2700 visitors to the site. I’ve had over 23,500 visitors total, most of them this year. I would love to hear from any science teachers or students that have found this site useful.

I look forward to seeing what my students come up with as they post about their topics. I’m encouraging them to do more than just a list of properties, to dig deeper and talk about the unusual stories and histories of each element or material. And now, I am pleased to introduce my chemistry students’ blog posts . . . .

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