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Archive for November, 2010

by Morgan Knapp

Guest Host

Mercury poisoning, as I’m sure you can guess, comes from contact with mercury.  Typical symptoms of mercury poisoning are: an itching or burning pain, swelling, skin shedding, high blood pressure, discoloration of the skin (see picture below), and an increase in saliva production.  “But how do I get mercury poisoning”, you ask. Well, you can get mercury poisoning from too much direct contact with mercury.  It is contained in some makeup, in some vaccines and medicines, amalgam teeth fillings, as well as broken fluorescent light bulbs, and of course fish.

mercury mottling

Mottled skin from mercury poisoning

Consumption of fish is the main source of mercury poisoning nowadays. It is hard for a fish to get rid of mercury in its system, so when it is eaten, the next fish up on the food chain collects the mercury from the fish being consumed. Therefore, the higher the fish on the food chain, the more mercury it is likely to contain. Tuna, whale and dolphin are fish that usually have high mercury levels. So it’s not good to eat large amounts of any of those fish. In fact the actor Jeremy Piven was diagnosed with a disease caused by mercury poisoning, from eating sushi twice a day for almost twenty years.  The earliest account we know of mercury poisoning was Qin Shi Huang. Qing Shi Huang was an emperor of China who took mercury pills that he believed would give him eternal life. But of course it did the opposite and killed him. Large amounts of people have been subject to mercury poisoning from improper use of it at schools, including students and teachers holding mercury in their bare hands and playing with it…not such a good idea.

Fish table

Amounts of mercury in different types of fish

Detecting Mercury Poisoning: The common way to test for mercury poisoning is taking urine or blood samples and evaluating them.

Prevention: If you happen to come into close contact with mercury, it is recommended to immediately wash your skin with soap and water, then go to a doctor for evaluation. Chelation is a process used to get rid of mercury and other harmful metal poisonings. There are different chemicals that are used for different types of chelation, but chelation is done by taking pills orally. Over time it reduces the amount of mercury in your body. Some people believe that some forms of autism is caused by mercury poisoning, and chelation has been used to try and cure those with autism. The medical field is skeptical of chelation and say that it doesn’t have much affect on anything. It hasn’t been proven to help autism either. Chelation is also very dangerous; it can cause kidney failure, cardiac arrhythmias, vomiting, nausea, and even death.  There have been more than thirty recorded deaths from chelation since the 1970’s.

The moral of the story is: be careful around mercury, because it is hard to cure mercury poisoning!

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Magnet activity

Shannon and Kenzie demonstrate magnets

I’ve written before about my views on student engagement and involvement in education; that students learn best when they are most engaged and involved in the educational process (here’s a link to a previous post on the subject). This is all based on 20 years of observation that I am usually the person who learns the most in my own classroom, simply because as I prepare materials to present to my students, I have to learn them very thoroughly myself, and as I teach these materials, I am making a type of commitment to the concepts; staking my own reputation that what I am teaching is correct. The gist of my philosophy is that if I can get students to become teachers themselves and fully commit to the concepts they are teaching then those concepts will never be forgotten. You could compare this to the old often-repeated adage:

Feed a man a fish, and you feed him for a day. Teach him how to fish, and you feed him for a lifetime.

To which I would add: Train a man how to teach others how to fish, and you feed a whole village for eternity.

A number of years ago, while teaching at Juab High School in Nephi, Utah, I began a program to take my advanced physics and Chem II students to the Nephi Elementary School once per month to present lessons to the classes. I worked with the teachers there to come up with lessons that fit into their curricula but also could be easily demonstrated. My students had to practice the demonstration, write up a brief 20-minute lesson plan with a handout, and receive feedback from their peers, myself, and the elementary teachers.

Cael and his vacuum pump

Cael demonstrates his vacuum pump

It wound up being one of the most effective projects I ever developed. My students were always a bit nervous the first time, but after seeing how excited the elementary kids were, they caught the same enthusiasm and soon were asking me when our next visit would be. They also presented these mini-lessons at a back-to-school night at the end of the year for their parents and other students to see. It was a definite win-win activity; both the elementary students and my students benefited greatly and it was worth all the effort we put into it.

Since teaching at Juab High School my teaching assignments have not allowed me to continue this program, although at Mountainland Applied Technology College my multimedia students did participate in the Mars Exploration Student Data Team program and presented at a symposium at Arizona State University in 2004. My students also created a two-hour documentary on the history of AM radio in Utah that aired on KUED, Salt Lake’s PBS station, in 2007. You could say that they were teachers and content creators from these experiences.

Now that I am back at a high school teaching science, I have reinstated the students-as-teachers concept through what I am calling the Walden Elementary Science Demonstration Program. I’ve even written a small grant for the Air Force Association last week to support this. On Friday, Nov. 12, I took my astronomy students down to the elementary classrooms at Walden to present lessons. Just as at Juab Elementary all those years ago, my students picked a topic and a demonstration, practiced it, wrote up a script or lesson outline, and then presented in the classes. I videotaped parts of the presentations and took photos. The elementary students were excited, engaged, actively getting their hands on materials, asking questions, and participating. My students did extremely well for our first time. Here are some of the presentations that they did:

Lunar Crater Activity

Annette and Olivia demonstrate lunar cratering

Shannon and Kenzie presented the properties of magnets and did a demonstration of a gravity assist maneuver using neodymium magnets and steel shot to represent planets and a space probe (I once got two neodymium magnets stuck up my nose while presenting this same demonstration to a group of teachers at the Jet Propulsion Laboratory. It’s a long story . . . .) Shannon and Kenzie had the challenge of adapting their lesson to be understandable for kindergarten students and for 4-6 graders (they presented twice). They demonstrated some large industrial strength iron horseshoe magnets I’ve had all these years and the kids had fun trying to pull them apart.

Cael and Koplin taught about how difficult it is for humans to survive in space, and demonstrated the properties of a vacuum by blowing up marshmallows. Cael’s father helped him construct a homemade vacuum chamber out of a Bell canning jar and a hand pump (very ingenious, actually, as you can see in the photo). Students had fun pumping out the chamber, seeing the marshmallows expand, and then releasing the valve and seeing them suddenly shrink again.

Olivia and Annette demonstrated how the surface of the moon formed using the lunar cratering activity (dropping rocks into a pan of flour and cocoa powder). They also tied it into a map of the moon, and had the kindergarten students repeat back what they had learned to win a prize – a piece of rice krispy treats coated with frosting to look like the moon’s surface.

Inertial scale activity

Scotty and Colman demonstrate the inertial scale

Scotty and Colman taught inertia and momentum by demonstrating the properties of an inertial scale I made a few years ago. It’s basically a metal ruler with a film canister at the end clamped down on a table’s edge. The more heavy a rock you place in the canister, the slower the ruler will vibrate due to the rock’s momentum. They also demonstrated dominoes, yanking a piece of silk out from under an object, etc.

Mars site selection activity

Maxson teaches about Mars landing sites

Maxson talked about the surface of Mars and how hard it is to find a good landing place. His partner wasn’t able to attend that day (he had an activity in another class that went unexpectedly long), but Maxson was able to fill in for his missing partner by having the 4-6 graders look for possible landing sites on maps of Mars.

Alexi and Erika presented the scale of the solar system to 1-3 grade students, showing them various balls that represented the sizes of the sun, Jupiter, Earth, Mars, etc. They also showed GoogleEarth. Then they took the students outside and had them stand in positions of relative distances for the planets. I didn’t get a chance to go outside and photograph that part of the activity, but I heard from the teachers that it went very well.

Scale of the solar system

Alexi and Erika demonstrate planetary scales

For me, the best part of doing these presentations is at the end of class when all my students gather back in my classroom to report on how it went. I wish I had had my camera running. They were telling each other what went right and wrong, what the elementary students had said and done, and I knew at that moment I had achieved my real purpose: my students were excited about science, and this was an experience they will never forget. As for the concepts they had to learn in order to make their presentations, I think it’s safe to say they will never forget them, either. I uploaded the photos I had taken to my laptop and did a slideshow at the end of class so that they could all see what the other teams had done. At the end of the year, we’ll do a video presentation as well.  Not bad considering I hadn’t told them about this until two days before their presentations, so that they had only two days to choose and prepare their lessons. They did great! Now in December my chemistry students get their turn.

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by Tanner Sorensen

A big part of the development of Alchemy originated in Islam. The word alchemy came from the Arabic word al-kimia, which came from the Persian word kimia. Will Durrant quotes in his book The Story of Civilization IV: The Age of Faith,

“Chemistry as a science was almost created by the Moslems; for in this field, where the Greeks (so far as we know) were confined to industrial experience and vague hypothesis, the Saracens introduced precise observation, controlled experiment, and careful records. They invented and named the alembic (al-anbiq), chemically analyzed innumerable substances, composed lapidaries, distinguished alkalis and acids, investigated their affinities, studied and manufactured hundreds of drugs. Alchemy, which the Moslems inherited from Egypt, contributed to chemistry by a thousand incidental discoveries, and by its method, which was the most scientific of all medieval operations.”

Alchemy poster

Alchemy Section from the Elusive Atom poster

There are many Islamic figures in chemistry, and they often aren’t as acknowledged as they should be. Early Islamic chemists such as Jabir ibn Hayyan, Al-Kindi and Al-Razi made important chemical breakthroughs such as perfumery; distillation apparatus; muriatic, nitric, acetic and sulfuric acids; purified distilled alcohol, soda and potash; and filtration.

Jabir understood the importance of experimentation. Jabir created the alembic when he discovered how to complete the process of distillation. Jabir’s teacher, Ja’far al-Sadiq, refuted Aristotle’s theory of four elements by saying “I wonder how a man like Aristotle could say that in the world there are only four elements – Earth, Water, Fire, and Air. The Earth is not an element. It contains many elements. Each metal, which is in the earth, is an element.”

Drawing of Geber

Jabir ibn-Hayyan, known in the West as Geber

Another influential Muslim chemist was al-Razi. Al-Razi was the first to distill petroleum, invent kerosene and lamps for it, invent soap bars and recipes for soap, make antiseptics, and developed many chemical processes like sublimation.

In addition to all other contributions, Muslim alchemists developed theories on the possibility of the transmutation of metals, the philosopher’s stone, and creating artificial life in laboratories, as in later medieval European alchemy, though these theories were eventually discredited and rejected by practical Muslim chemists from the 9th century thereon. Therefore, medieval Arabic alchemy was the biggest contributor to Alchemy and Chemistry as we know it today.

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