Archive for the “chemistry” Category

Melting Cubes: A Discrepant Event

Today is Labor Day (thus the casualness of it all) and my son and his friend were shooting some video segments of, well, shooting as well as backwards slow motion (see http://www.youtube.com/user/YouKnowMeHy). I asked them to film a demonstration I did this week at an inservice professional development workshop I did for middle grade teachers.

My son filmed with his little Sony Cyber-shot camera (a still picture camera that also does video) and then edited it with Apple’s iMovie.

For another discrepant event please visit my blog posting on surface area to volume ratio.

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Especially in the winter months, I enjoy a good cup of strong, hot coffee. So I purchased the 12V and USB Travel Mug from ThreeSixty Lifestyle. It is a nice looking mug with a cover but on my first use, it didn’t seem like it really was adding any heat to the coffee.

So I got out my probeware and Spark (from Pasco) and put it to the test. First, I determined that the coffee in our coffee pot is 80° C (degrees Celsius or 176° F ).  To test the mug, I filled it almost full (350 mL) with water at about 80° C (beverage heating for 12 ounces in our microwave) without plugging into my USB. Then I dumped this out and started again and I tested it with 80° C water with it plugged in.

From the first graph, after about 80 minutes it had a temperature of 46° C. From the second graph it kept a constant temperature of 60° C after

Graph 1: Cooling Curve with No Electrical Heating

falling for the first 28 minutes. So clearly heat is being added with an equilibrium (heat lost=heat gained) established at 60° C with a room temperature of approximately 20° C. But is it worth the bother to plug it into my computer and have a tethered cup? Without heating the cup, the

Graph 2: Cooling Curve with USB Electric Heating

water stayed above 60° C for approximately 30 minutes. It seems like both cups took about the same amount of time to cool to 60° C so there is no advantage for my first cup of jo in the morning, as that usually doesn’t last 30 minutes. Later in the morning, when I tend to let the coffee sit longer, it might pay to have it plugged in. But coffee at 60° C doesn’t give me that coveted deep-warming feeling. So good thing I bought this at Big 5 Sports, as they are quite good at accepting returns.

When it comes down to it, I would like to find a coffee heater that has a

"Melting and Boiling Points: Heating Curve"

Image from "Melting and Boiling Points: Heating Curve" from Adaptive Curriculum

heating curve, rather than a cooling curve.  Perhaps I need a hot plate, like the one shown in the image from Adaptive Curriculum to the right. Bring on the heat!

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Here is a hot list of the titles in this blog on science education and technology for 2010:

Ice Candle and Specific Heat, December 30, 2010

Science Prezi-tations: A Break from PowerPoints, December 22, 2010

Sounds for Science Educators, November 27, 2010

Great Science Teaching: An Iterative Process, October 25, 2010

Report To The President Prepare And Inspire: K-12 Education In Science, Technology, Engineering, And Math (Stem) For America’s Future, October 21, 2010

Engaging Starts and Video of Class, October 1, 2010

Titles for 2010 www.ed-tech-4-science.com, a blog about science and technology were placed into Wordle

Titles for 2010 www.ed-tech-4-science.com placed into Wordle

The Context of Learning and Learning with Style, September 15, 2010

Animals in the Science Classroom, August 29, 2010

What is Science? July 31, 2010

Readers and Science Education, July 12, 2010

Electric Cars, Tesla, and Sustainability, June 28, 2010

Sports Drinks, Young Athletes, and Summer Heat, May 29, 2010

Guided Inquiry and Surface Area to Volume Ratio, May 26, 2010

Happy Earth Day, April 22, 2010

Scale of the Universe, April 10, 2010

NSTA Presentation, March 19, 2010

SMALLab Physics, March 3, 2010

My Mendel Moment and a Review of Sprout & Grow Window, February 8, 2010

Testosterone and Who We Are, January 20, 2010

Science and the Haitian Earthquake, January 18, 2010

Science Shows by Undergraduate Students, January 13, 2010

“After Armageddon” on the History Channel, January 5, 2010

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When it comes to gift giving, I suspect that science teachers tend to give gifts with richer science experiences than most other people. This is sometimes but not always appreciated, so moderation is required. This Christmas, my wife was the recipient of the “Mathmos Thaw” ice candle from think-geek.com. My iphone picture to the right shows the beauty of a candle shining through about ½ inches of frozen water.

One thing that science teachers appreciate more than your everyday person is the extremely high specific heat capacity of water. The high specific heat capacity of water has great demonstrations (for example “Flaming Hands”) and all sorts of implications such as more moderate climates when living near a large body of water and why water is so good at putting out fires. Adaptive Curriculum just released a new Activity Object entitled “Specific Heat.” Through a series of virtual experiments, students are led to an understanding of the amount of heat transferred or absorbed (Q) = mass (m) x change in temperature (∆T) x specific heat (c).

This Activity Object from Adaptive Curriculum is a fantastic way to help students develop a deep understanding of concepts related to heat transfer that are important in both physics and chemistry.

* * *

Time lapse Mathmos Thaw From Think-Geek.com

“Thermodynamics is a funny subject. The first time you go through it, you don’t understand it at all. The second time you go through it, you think you understand it, except for one or two small points. The third time you go through it, you know you don’t understand it, but by that time you are so used to it, it doesn’t bother you anymore.” Arnold Sommerfeld (1868-1951) From:  http://www.eoht.info/page/Arnold+Sommerfeld

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The President’s Council of Advisors on Science and Technology prepared a report (September, 2010) with the following recommendations:

(1) STANDARDS: SUPPORT THE CURRENT STATE-LED STEM ReportMOVEMENT FOR SHARED STANDARDS IN MATH AND SCIENCE

(2) TEACHERS: RECRUIT AND TRAIN 100,000 GREAT STEM TEACHERS OVER THE NEXT DECADE WHO ARE ABLE TO PREPARE AND INSPIRE STUDENTS

(3) TEACHERS: RECOGNIZE AND REWARD THE TOP 5 PERCENT OF THE NATION’S STEM TEACHERS, BY CREATING A STEM MASTER TEACHERS CORPS

(4) EDUCATIONAL TECHNOLOGY: USE TECHNOLOGY TO DRIVE INNOVATION, BY CREATING AN ADVANCED RESEARCH PROJECTS AGENCY FOR EDUCATION

(5) STUDENTS: CREATE OPPORTUNITIES FOR INSPIRATION THROUGH INDIVIDUAL AND GROUP EXPERIENCES OUTSIDE THE CLASSROOM

(6) SCHOOLS: CREATE 1,000 NEW STEM-FOCUSED SCHOOLS OVER THE NEXT DECADE

(7) ENSURE STRONG AND STRATEGIC NATIONAL LEADERSHIP

The report begins with this summary of the importance of STEM:

The success of the United States in the 21 century – its wealth and welfare – will depend on the ideas and skills of its population. These have always been the Nation’s most important assets. As the world small measure by the effectiveness of science, technology, engineering, and mathematics (STEM) education in the United States. STEM education will determine whether the United States will remain a leader among nations and whether we will be able to solve immense challenges in such areas as energy, health, environmental protection, and national security. It will help produce the capable and flexible workforce needed to compete in a global marketplace. It will ensure our society continues to make fundamental discoveries and to advance our understanding of ourselves, our planet, and the universe. It will generate the scientists, technologists, engineers, and mathematicians who will create the new ideas, new products, and entirely new industries of the 21st century. It will provide the technical skills and quantitative literacy needed for individuals to earn livable wages and make better decisions for themselves, their families, and their communities. And it will strengthen our democracy by preparing all citizens to make informed choices in an increasingly technological world.

Chapter 5 focuses on teachers and begins with this statement:

Anyone who has set foot in a classroom knows that teachers make a huge difference in the lives of their students. While not everyone can recall the influence of a legendary teacher like Jaime Escalante, many people have stories about the crucial role that a teacher played in sparking their passion for a subject, teaching them a lifelong skill, or helping them surmount an obstacle. Indeed, most people who work in STEM fields or who simply have an interest in STEM can point to teachers who excited about them about the beauty and power of mathematics, the wonders of science, or the power of technology – and who helped them learn that they could gain mastery of these subjects. Sadly, though, many adults also point to experiences in school that convinced them that STEM subjects were inherently boring, cryptic, or beyond their grasp.

The report correctly points to the importance of STEM for our nation, and suggests compelling steps to improve what we do.

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A recent New York Times article (September 8, 2010) created a stir by suggesting that the old advice to do homework in the same spot in the home was incorrect. Benjamin Carey summarizes the findings of cognitive scientists as “instead of sticking to one study location, simply alternating the room where a person studies improves retention.” Providing evidence that takes to task the one study place idea, Carey writes: “In one classic 1978 experiment, psychologists found that college students who studied a list of 40 vocabulary words in two different rooms — one windowless and cluttered, the other modern, with a view on a courtyard — did far better on a test than students who studied the words twice, in the same room. Later studies have confirmed the finding, for a variety of topics.”

Most kids aren’t going to rejoice in this news. They are holding out for the research that says that it helps them to do homework if they are also watching TV. I guess if there are parents who make their children go to some solitary confinement place to do homework, the children might be happy to see this news. My sons seem to enjoy doing their work in the kitchen/family room area, where we tend to congregate, and my wife or I are available to help. They do have a built in desk/office space that has no windows and is cluttered. I was thinking about clearing some clutter so they would actually use their desk area, but now I can point to this 1978 study as evidence that their desk area is perfect. To be honest, I don’t really mind where they do homework and study, just as long as they do it.

Extending this idea, the varied environments created through virtual learning are better than nuclear submarine fission“different rooms.” Students can learn while on Mars or learn while at the bottom of the ocean. Just consider some of the over four hundred Activity Objects of Adaptive Curriculum, students find themselves as mechanics in a car garage, on planets from different solar systems, in Egypt studying mutualism, in a chemistry lab, in a music salon, controlling a reactor in a nuclear submarine, at an amusement park constructing a roller coaster, living in Europe 500 years ago, and producing a theatrical production. Clearly my house doesn’t have rooms that are this interesting, my advertisement might be, “you can wash dishes in the kitchen.” Actually, we do make an effort to have an interesting home environment with interesting décor from different places around the world where we lived, a pool, a trampoline, a basketball court, a lawn, two fish tanks, a reptile tank, two sulcatta baby tortoises, one shelty, and an exercise area. My home, just like most other homes, is more interesting than the typical classroom. The beauty of virtual science activities is that we can take students out of the classroom. I don’t mind an occasional replication of a classroom lab, but the true power of virtual learning is taking students outside the walls of the classroom.

I hinted at controversy in my opening sentence. The Times article also called the whole notion of learning styles a myth; A dangerous statement with so many teachers eating up the invented multiple intelligences of Howard Gardner. I predict in 2020, Gardner will state that there is an intelligence for creating new multiple intelligences. While it is clear that some people are better at some things than other people are, at what point do skills, abilities, and knowledge become grouped as intelligence? I think I should rush to invent “soccer intelligence,” “volleyball setting intelligence,” and “interior design intelligence.”

The great regard for Gardner’s work by teachers is no doubt because teachers see different learning styles. Any teacher who has taught for several years will know that students have varied learning styles. Come on, how obvious, some students learn quite well by reading a textbook and others simply don’t. If you have ever been in school and there was a subject that didn’t come naturally to you but did come naturally to others, you would also realize this. So, I’m not sure how you can state that, “The contrast between the enormous popularity of the learning-styles approach within education and the lack of credible evidence for its utility is, in our opinion, striking and disturbing.”

Color Mixing: Paints and Lights

Color Mixing at a Theater: Paints and Lights

To be sure, a teacher with only a dry-erase marker and a class of 35 adolescent students might have a difficult time adjusting to the learning styles of students, so we might expect little “utility” as he lectures. But if given the training, resources, and a suitable class size, teachers can know their students better, and plan a variety of experiences to help students learn science. One powerful tool for helping students learn at their own pace, and in ways they enjoy, is internet-based science experiences.

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Both of my sons are competitive soccer players. When you live in Phoenix, AZ and you see young athletes running and sweating on a hot day for a prolonged period of time, it is easy to conclude that they would benefit from a beverage with electrolytes and some sugar. The electrolytes replenish the salt that is lost in sweating, and can thus prevent muscle cramping, with the most important ion being potassium. Young competitive soccer players also have very little body fat, so the sugar gives their body energy.

I confess, I went through a Gatorade, PowerAde, and Propel stage for our boys. My oldest son prefers Gatorade, my youngest Propel, and PowerAde was often the least expensive. When I would grocery shop I would always stop on this aisle to see if there were bargains to be had, and then I would stock up. The drinks, made by either Coca-Cola or Pepsi, contain electrolytes and sugar so they seemed to be meeting these basic needs. I like the clearness of the Propel, in that I prefer to not have artificial colors sweating out of the pores of my children (which I never understood why Gatorade thought this was an appealing commercial). Tedd Gorden, of MSU, describes the pros and cons of different formulas for sports drinks.

On hot days with long games or practices, we would send our sons with a large water container and a bottle of a sports drink. Their bodies seemed to tell them what was best, and they always drank far more water than the sports drinks. I have now moved to natural alternatives, so our oldest son is drinking Martinelli apple juice (which he says is the best tasting and comes in a fun round bottle) and our youngest Welch’s grape juice from 10 oz containers. The juices are about the same prices as the 32 oz bottles of sports drinks. So per volume, they cost three times as much, but per outing they are about the same.

If you could design your own sports drink what would it have in it? This intriguing idea is used by Adaptive Curriculum to engage students in the Activity Object “Osmosis.” From this engagement, students examine red blood cells in isotonic, hypertonic, and hypotonic solutions. Then students place raw eggs with the shell removed into different unknown solutions and then label what the solution must be based upon the weight gain or loss in the eggs. The Activity Object has a great engagement with multiple strong interactions. And when it comes to sports drinks, hypotonic solutions are best, whether it is made by Coca-Cola, Pepsi, or grown on a tree.

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One of the major themes that runs through many facets of science is the notion of surface area to volume ratio. I remember being a Peace Corps Volunteer in Kenya and using an experimental, guided-inquiry curriculum, inspired by the British Nuffield science program. Students made plasticine cubes of various sizes. I’m not sure why British people have an aversion to clay, but plasticine seems to be their school sculpting material. Then students measured the surface area of the cubes and calculated the volume. Then they calculated the surface area to volume ratio and discover that the larger the object, the smaller the surface area to volume ratio.

Which helps to explain many types of adaptations in biology and why individual cells can’t be the size of houses; they would simply not have enough surface area to absorb the materials they need, like oxygen, or to expel waste. From villi in the intestines to convolutions in the brain, our bodies have many adaptations to increase surface area.

Adaptive Curriculum has a guided inquiry Activity Object called “Surface Area to Volume Ratio in Organisms.” A clever engagement draws the students into the interactive experience. You have a plate of cheese with different size cubes that you are going to put into the microwave. But first, learners predict whether the large cubes or the small cubes will melt first.

Obviously, the small cheese cubes will melt before the larger ones. If you thought this, you have experienced a discrepant event. In actuality, the large cubes melt first. Since the microwave heats from the inside, the smaller cubes lose their heat faster than the large ones. The larger cubes, thus retain more heat and melt faster.  Discrepant events are powerful, because learners want to know why they were wrong.

From this, learners virtually change the size of cubes and see the changes in surface area, volume, and surface area to volume ratio. Then body sizes and shapes of animals are explored, as students learn about the implications of size and shape for heat loss.

My Peace Corps teaching and Adaptive Curriculum are different modes of guided inquiry and discovery learning, but both can help produce deep and life long learning.

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When I was doing my sabbatical at the University of San Carlos (Cebu, Philippines), Ed Van den

fire-tornado

Berg (one of the really great guys in science education), would have the undergraduate secondary education science students put on physics and chemistry demonstrations for the local school children. It was a delightful way to give them experience teaching and expose children to the interesting world of science. In the picture, two of my students demonstrate their fire tornado. (See http://www.west.asu.edu/rillero/philippines.htm for more of my photographs from the Philippines.)

In this YouTube video below, a similar program is described called “The Little Shop of Physics.”


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Tonight, as I understand it, “After Armadeddon” will air at 8 PM on the History Channel. It does present interesting opportunities for science teachers to talk about student ideas and feelings related to future and past disasterous conditions on Earth. It is part of a week of disasters at the History Channel. Here is a description of the show:

hy-tv-desert-sceneTuesday, January 05, 2010
After Armageddon: – 08:00-10:00 PM

What have past acts of destruction taught us about what will happen to mankind after the apocalypse? Is it inevitable that disaster will someday strike America on an unprecedented level? How has history prepared us? History’s most dramatic events–Hiroshima, 9/11, Hurricane Katrina and others–are examined and analyzed with hard data gathered from their massive aftereffects. The disappearance of water and food supplies, the effects of deteriorated sanitation and health care on the remaining population, and the increased use of violence as a means of survival–all illustrate how societies have responded and survived.

I have an especially keen interest in this show as my son, Hy Rillero, spent just over two-weeks filming his segment, with many long days of work. I am hoping that much of his vignette survives the editing process for this two-hour special. No matter what happens it was a great experience for Hy to work with Director Stephen Kemp (
Raw-TV). In Hy’s section, a respiratory virus has wiped out 80% of the US population and he chronicles his family’s quest to survive.  The photo is of Hy and his film mom and dad.

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