Teacher resources and professional development across the curriculum

Teacher professional development and classroom resources across the curriculum

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Reactions in Chemistry
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Sub Image2:Macro to Micro Structures
1) Atoms and Molecules2) Macro to Micro Structures
3) Energetics and Dynamics4) Theory and Practice in Chemical Systems5) Chemical Design6) The Chemistry of Life7) Chemistry and the Environment8) Chemistry at the Interface

Unit 2.2 Observing Change
This unit emphasizes the important role of observation in science and how observations can be related to structures and processes on the microscopic scale.
Video program cues: 4:15 — 14:05

Observing magic

“Hello, my name is Alain Nu, Mystery Expert. You may ask yourself what a mystery expert is doing in Reactions in Chemistry — well, it just so happens that the word 'mystery' is in the word 'chemistry'. And so, to give you an idea of mysteries in chemistry, let me give you a couple of my own thoughts about mystery. You see, people are curious about mystery not because of its information but because of its lack of information. Unlike a puzzle that remains to be solved, the beauty of mystery is experiencing that which is unsolved, and perhaps the notion that things are not always as they appear.”

Alain Nu
Mystery Expert

Kimbrough, D.R. and DeLorenzo, R. (1998)' Solving the Mystery of Fading Fingerprints with London Dispersion Forces, 'Journal of Chemical Education, Vol. 75, No. 10, pp: 1300-1301.

Camacho-Zapata, R. and Lopez-Garriga, J. (2000)' ‘Integration of Pre-college Chemistry Education and the GLOBE (Global Learning and Observations to Benefit the Environment) Program’, 'Journal of Chemical Education, Vol. 77, No. 12, pp: 1586-1589.

Visualizing the microscopic
Teachers' forum

“When we started this whole thing, someone commented about seeing the atom. We all know that you have never seen an atom; that has never occurred. And on a physical level we never can. So, to get them to understand that it is all representational, is [to explain] basically that we have got a good story which seems to work, but that we toss it out every time that it quits working. This is implicit, to get from the large scale to the small scale, to understand that it is a good story.”

Tom Pratuch
Annandale High School, Virginia

“[We need] to emphasize that these stories that we have are logical explanations of what has been observed and to warn them not to learn chemistry but to understand chemistry, because, if we observe something new that does not fit in with our preconceived notions, we need to change the story so that it is logically consistent with what we have observed.”

Dr. Michael Clarke
Duke Ellington School of the Arts, Washington, D.C.

“A lot of times it is the job of students come up with analogies that address the invisible, like when they see a picture taken by an electron microscope, you may talk about how you might make a hand-print in clay, or — do you remember that device with all the pins? You could put your hand in and it could keep the shape of your hand. When you see the shape, are you really seeing the hand? Is your hand really there? This helps the students develop what we had already developed for ourselves.”

Veatta Berry
Thomas A. Edison High School, Virginia

“One big misconception that kids have is that the air is actually not there; that there is nothing around us. If you have one of those scales, you could put two balloons on it and they balance out… then you fill one with air. The kids are convinced that the balloons will still balance out. That’s a really concrete way of showing them that the air is really there.”

Gannon Sugimura
Annandale High School, Virginia

“Sometimes challenge them to figure out a way to show something that you’ve identified as a misconception and get them to discuss it.”

Sharon Walton
Watkins Mill High School, Maryland

“On the first day of class, what I focus on is letting them do something.”

Tom Pratuch
Annandale High School, Virginia

“Really it’s thinking about… as a teacher, how you understand chemistry yourself. What do you really picture in your head, and thinking how you are going to get the students to see the same picture. I tell my kids that I see particles moving around in my head; I have this picture, I see it. I know you don’t, so I’m going to help you see it.”

Veatta Berry
Thomas A. Edison High School, Virginia


Wilson, E. (2000)' Single Molecules React Via Microscope Tip, 'Chemical & Engineering News, Vol. 78, No. 40, pp: 13-14.

Niaz , M., (1999) Should We Put Observations First? Journal of Chemical Education, Vol. 76, No. 6, pp: 734.

JCE Classroom Activity #28, (2000)' More Than Meets the Eye: Nonvisual Observations in Chemistry (Gettys, N.S. and Jacobsen, E.K., eds.), 'Journal of Chemical Education, Vol. 77, No.9, pp: 1104A-1104B.

Glue-Ball Laboratory

Felix Muhiga introduces the observation of chemical change.



How to teach for thinking

“The bottom line is that we’re there not to make them chemists, but to teach them a way of thinking.”

Tom Pratuch
Annandale High School, Virginia

"Along the line that you try to teach them a way of thinking, and how you figure out what something is when you can’t even see it. You get shoe boxes and put some different kinds of objects in them, like bolts and ping-pong balls or a brick, and pass those boxes out and have them not being able to open, but shake them around and let them observe. From their observations, try to figure out what kind of thing is in there. Explain how people, because of the background they had, came to an understanding of what the atom is like.

Irene Walsh
St. Andrews Episcopal School, Maryland

"I traditionally started out the first year of chemistry course with the old candle study: write out as many observations as you can. It’s usually a homework assignment the first day. We go through an observation, talking about it being quantitative and qualitative. Then we start talking about what’s burning. They list the regular things: the candle is burning, the air is burning. Then we successfully go through a logical reasoning to prove that nothing is burning. Then, we go back and collect some more physical evidence like passing a note card in the flame and finding it’s hollow. We come up with a list of observations, which is a couple of pages long, and they’re just amazed, because they don’t sit and think about the world around them. They subsist in it but they don’t think about why things are the way they are, what things are made up of. At the end of this conversation, they start to talk about all these things about the candle that they hadn’t ever thought about. I tell them that there is a whole book written about the burning of the candle… and they just can’t believe it.

Caryn Galatis
Thomas A. Edison High School, Virginia

Research, Discovery, and Education (2001) editorial in Journal of Chemical Education, Vol. 78, No.4, pp:431

Goodisman, J., (2001) Observations on Lemon Cells Journal of Chemical Education, Vol. 78, No.4, pp:516-519

Proceed to Unit 2.3 arrow

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