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Posts Tagged ‘element properties’

Element ornaments made by chemistry students at Walden School of Liberal Arts

Element ornaments made by chemistry students at Walden School of Liberal Arts

Leading up to Winter Break, we were learning about the elements and their properties in my chemistry class at Walden School of Liberal Arts. It seemed a good time to have my students pick an element to research and find out more about, but I didn’t want to have them do the “standard research paper.” I also wanted this project to incorporate some type of art as we are continuing on with the STEM-Arts Alliance program.

I decided to try out an activity that one of our former teachers at Walden, Matt Ellsworth, used last year: have the students pick an element and create an “ornament” that reflects something about the element, such as an outstanding property, a commercial use, its form as a mineral, etc. He also had them write physical values of the element on the ornaments, such as electron configuration, symbol, atomic number, atomic weight, and so forth.

My chemistry class is small, so not a lot of ornaments were made, but the results were overall quite good. As you can see from the photo, the ornaments incorporate some interesting designs and 3D effects. For example, the ornament of the space shuttle is for beryllium because that element was used in the brake linings and window frames of the space shuttle. Beryllium is mined principally in western Utah in the Spor Mountain range. An even more characteristic use would be to design the ornament to look like the James Webb Space Telescope, since its primary mirror is made from Utah beryllium.

A synthetic bismuth crystal. Notice the play of colors across its surface.

A synthetic bismuth crystal. Notice the play of colors across its surface.

The ornament on bismuth is very well done – it shows the structure and iridescent coloring of a single bismuth crystal. I’ve photographed bismuth crystals very much like it on display in Theo Grey’s office in Urbana-Champagne, Illinois. He is a noted collector of the chemical elements, the author of a photographic table of the elements, and creator of the best-selling iPad periodic table app. He was very accommodating to allow me to interview him in his office (sitting at his hand made wooden periodic table conference table) on my way home from Philadelphia in 2009.

This makes a great high-interest activity to do when students start to get restless before Winter Break. They can be quite creative in how they design and build their ornaments, and each year you can save the best ones to display. We simply used unfolded paper clips to hang them in class, and construction paper, scissors, glue, and tape to put them together.

You could also combine this with making ornaments from crystallized supersaturated salt solutions, such as copper (II) sulfate or Epsom salts (magnesium sulfate). Just look up the solubility of the salts and make a saturated solution, then bend some pipe cleaners in desired shapes representing the various holidays of Winter Break, such as the Star of David, or representing chemistry shapes (a Florence flask, a test tube, a beaker, etc.). Make a hook and hang the shape from a pencil in the solution, making sure not to touch the sides or other ornaments. After a few days, after crystals have formed, the ornaments can be removed and dried. We weren’t able to get to this activity, which I first learned about from a Flinn Scientific lab. But I have the materials and will try it next year.

More Elemental Ornaments: From Upper Left clockwise: A helium balloon, a titanium ring, a copper atom, a xenon buib, a particle accelerator with an argon chamber, a quartz crystal made of  silicon dioxide, an iron horseshoe magnet, a lead pipe, nitrogen gas in the atmosphere and fixated in the soil, a gold chain, a tungsten light bulb filament, a sack of coal (appropriate!), and, of course, Freddie Mercury.

More Elemental Ornaments: From Upper Left clockwise: A helium balloon, a titanium ring, a copper atom, a xenon buib, a particle accelerator with an argon chamber, a quartz crystal made of silicon dioxide, an iron horseshoe magnet, a lead pipe, nitrogen gas in the atmosphere and fixated in the soil, a gold chain, a tungsten light bulb filament, a sack of coal (appropriate!), and, of course, Freddie Mercury.

Another idea would be to use mineral samples as ornaments – with thin wire you can create a cage for a small sample of quartz or calcite or some other crystalline mineral to hang as an ornament. With some good epoxy glue you could attach a hook directly to a crystal. Of course, such mineral samples could also be used as jewelry (necklaces, earrings, etc.). A final idea could be to use some unvarnished copper sheeting or brass sheeting to cut ornament shapes, then use chemicals to create a patina on their surface. For example, if you leave copper and brass in a sealed container with ammonia and salt, they will turn nice blue color. If left in a container with vinegar and salt (or evan salt and vinegar potato chips crumbled up with a little extra vinegar added) the copper and brass will turn a nice green color as copper acetate forms.

Update: Another year has come and gone, and I had my chemistry students do the same activity this year. The class was larger, and there were some great results, including some interesting origami, as you can see from the photo here. Some were obvious, such as a black tube of paper as a lead pipe. Others were more creative, including a sack of coal for carbon, a particle accelerator for argon, and my personal favorite, Freddie Mercury.

A ChemisTree, complete with Elemental Ornaments.

A ChemisTree, complete with Elemental Ornaments.

Shapes cut from sheets of copper and brass, treated with vinegar and salt (green patina) and ammonia and salt (blue patina).

Shapes cut from sheets of copper and brass, treated with vinegar and salt (green patina) and ammonia and salt (blue patina).

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Gay eyeballs

Making gak eyeballs at Walden School

This last week was our final week of Fall Semester at Walden School, and for their final test my chemistry students planned, practiced, and presented chemistry demonstrations to their peers and to Walden’s elementary classes. Altogether five groups of students presented to the elementary school on Wednesday, Dec. 15 and the rest of the student teams presented on Friday, Dec. 17.

I’ve discussed my rationale for doing this in previous posts: that this is an excellent method for generating excitement about STEM in elementary students as they see their older siblings and high school students working with and presenting science. Certainly the younger students were very excited and attentive; they were eager to participate and asked good questions.

Raising hands

Students at Walden School participating in chemistry demonstrations

For me, though, the real reason for doing anything in my classes is always how it will benefit my students. Taking 3-4 days out of our curriculum to practice and present these demonstrations is hard to justify unless it has strong pedagogical advantages. The justification is this: as my students write up their demonstration scripts and outlines, as they practice talking about the science they are presenting, and as they prepare to answer questions from the audience they are thoroughly learning the chemistry behind their demonstrations. They are going beyond hands-on labs to share what they have learned, and that learning will be indelible.

Karlie and Sofia

Karlie and Sofia demonstrate hand warmers

The topics of the demonstrations had to related to the individual element/materials research project of one of the group members, which they are continuing to work on. Here’s what was presented:

Sofia, Karlie, and Jerry demonstrated the principles behind hand warmers by showing the rapid crystallization of sodium thiosulfate crystals that had been heated and then cooled down. They also talked about crystals in general.

Making gak

Mari and Casey help students make gak

Ryan and Casey, with help from Chelise, Lindsey, and Mari, demonstrated how to make gak (a polymer made out of white glue and borax powder). This is an old standby demonstration, and the kids really enjoyed it.

Copper demonstration group

Genny, Rachel, Jared, and Morgan demonstrate copper's properties

Genny, Rachel, Morgan, and Jared demonstrated aspects of copper chemistry. They handed around samples of copper ore (Rachel’s uncle is an engineer at Rio Tinto’s Bingham Canyon Mine in Utah) and showed a methanol version of a flame test (including copper salts). Jared demonstrated the alchemist’s dream reaction: turning copper into gold (actually brass).

Kinesthetic activity

Sid and Sam use a kinesthetic activity to demonstrate magnetic induction

Sam and Sid, with help from Josh, presented the idea of magnetic induction and discussed how modern electrical generators work. Sam actually built her own alternator and induction coil, and Sid presented on his research about the use of wind power to generate electricity. They also created a fun kinesthetic activity to show induction.

Burning magnesium

Karl and Nicona demonstrate burning magnesium

Karl, Nicona, and Tanner presented on the properties of the elements; they did a flame test as well, and demonstrated what magnesium ribbon looks like when burned and how fireworks get their colors. They also had sparklers for each of the students to try out.

Cabbage pH

Sonora, Dallas, and Morgan demonstrate cabbage pH

In class on Friday, the other groups presented their demonstrations. Sonora, Morgan, and Dallas presented the red cabbage pH demonstration that is one of my favorites.

Untarnishing silver

Mari and Holly demonstrate how to un-tarnish silverware

Courtney, Holly, and Mari showed how to untarnish silver using baking soda and aluminum foil. They even included a correctly balanced chemical equation, although we won’t be learning about those until we return in January.

Dry ice group

Libby, Lindsey, and Chelise demonstrate the properties of carbon dioxide

Chelise, Lindsey, and Libby presented the properties of carbon dioxide gas and dry ice. They showed how regular matches go out in carbon dioxide, but that magnesium burns even brighter when placed in carbon dioxide.

Olivia and Jace

Jace and Olivia explain the ingredients of gunpowder

Jace and Olivia talked about gunpowder, how it is made, and why it is dangerous. Jace has experience working with black powder (he has his own muzzle loader – this is Utah, after all) and he created some raw gunpowder, which he burn outside. They also demonstrated the “fire writing” demonstration of drawing on a piece of paper with a saturated solution of potassium nitrate, then touching a wooden splint to the edges of the writing to see it burn letters through the paper.

Josh and Jess

Josh and Jess demonstrate the principle of density with salt solutions

Josh and Jess presented on salt solutions and how they can be used to determine the density of objects. They showed how an egg will sink in pure water but will float in salt water.

We also videotaped as much of the presentations as we could and took quite a few photos; those students that weren’t helping present helped with the photography.

Burning gunpowder

Burning gunpowder

When their demonstrations were done on Wednesday and Friday, my students were excited about what they had done and the feedback they’d gotten from the younger students. They still have to learn some showmanship and presentation skills (which we’ll continue to work on), but based on what I saw and what the elementary teachers reported, the science content was excellent. They and their peers filled out evaluation forms (and I will as well) so that they can improve on their presentations for the next round in January.

Golden pennies

Golden pennies

It was a lot of work to prepare for this. Now my lab room is a mess and I’ll need to take a day during Christmas break to clean up and re-organize (and I think I forgot to throw out the leftover red cabbage pulp that’s in my trash can, so I’d better go clean up tomorrow). But despite the work and the lost time, I’d say these demonstrations were well worth it. As we go through the second semester, the students will present at least twice more, including a final time at a back-to-school night for their parents. We’ll polish the delivery, add more science explanations, create slide shows and videos to supplement their demonstrations, and by the end of the year these will be incredibly well done.

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