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Borneo Day 5: Tuesday, July 25, 2017

Country lane near school

The country road leading to SMAN 1 Mandastana.

On our second day at SMAN 1 Mandastana, I was faced with a bit of a challenge. During my presentation yesterday on my school (American Academy of Innovation) I showed slides of my students doing chemistry demonstrations, including the well-known flame test demo, where nichrome wires are dipping into solutions of potassium, lithium, sodium, calcium, barium, strontium, and copper salts, then heated in a Bunsen burner flame. These elements have fairly simple quantum structures (one or two electrons in an outer shell) and emit very definite colors. As the electrons are heated up, they absorb energy from the flame and jump to specific higher quantum levels. They then emit the same wavelengths of light as they fall back down to their ground states.

Doing flame test lab

Doing the flame test lab with chemistry students at SMAN 1 Mandastana near Banjarmasin in Southern Borneo.

The students asked, through Nazar, if they could do the same lab. My response was, “I don’t know – let’s look and see what you have and maybe we can.” I didn’t want to commit the chemistry teacher to do a lab, but she seemed willing, so we looked through her supply of chemicals after the class and found cupric sulfate, sodium chloride, potassium chloride, and barium sulfate. No lithium or strontium, which give off the best colors, but at least these four will work. Then we looked at her equipment. She has a lab assistant, and we unlocked the cabinets in her storage room. They have one nichrome wire, alcohol burners, and a good supply of beakers. So we could make this work.

So this morning I went to the chemistry classroom first thing, about 45 minutes before the students were to come in. The teacher got out the chemicals, and I discovered something interesting: none of the chemicals had been opened, not even the sodium chloride. The equipment also appeared to be unused – not brand new, as the storage cabinet had some dust on it, but sitting there for I don’t know how long. No stains on the beakers, and the alcohol burners had never been lit. We had to scrounge around to find a cigarette lighter. At least the container of alcohol for the burners appeared to have been used – about 1/3 of it was gone.

Flame test 2

David Black helping students with the flame test lab at SMAN 1 Mandastana near Banjarmasin in Southern Kalimantan.

Now I know this is not the norm throughout Indonesia, as I had seen the Assistant Principal at the elementary school we visited do the Priestley Experiment, the chemistry equipment at the SMAN 8 Jakarta school was well-used, and I found out later that other teachers saw science experiments being done at their host schools. So I don’t know why the equipment and chemicals have not been used here. The teacher certainly knows her stuff, as I saw from the class the previous day when the students were taking notes on mole fractions. And she is very willing to do this lab. So it seems to me that she either hasn’t had the training/professional development of how to conduct labs and use her equipment or she is unwilling to use up her supplies.

It also appears to me that the chemicals and supplies were part of a package provided by the central government, with a set list of materials. As chemistry classes go, she was fairly well supplied, but the chemicals were stored inside the fume hood as well as underneath, and the hood looked as if it might not function or be hooked up properly. The school is 20 years old and all the sinks in the chemistry lab were rusted out and nonfunctional, so that I had to get water for my solutions from a container on the counter. It was not possible for me to inquire further to see if this condition is general throughout Kalimantan Selatan or other provinces, but I guess that this might be a common problem in rural schools in Indonesia. After all, it is a common enough problem in the United States. Many teachers in both countries do not do the types of inquiry labs that students need to understand the practical side of chemistry.

David with chemistry teachers

David Black posing with the chemistry teachers (left) and English teachers (right) of SMAN 1 Mandastana. I really need to get my name tag straightened out . . .

Once I had the solutions made, I lit an alcohol lamp and saw that its flame was orange, not the blue I’m used to in Bunsen burners or with methanol. But with repeated dipping and heating, the colors were visible except for the barium, which is always the hardest one to see. We were able to find or make five wires, and divided the students into five groups. They traded off the four solutions. I told them what the five chemicals were and what colors to expect. I found that most of the elements are named the same in Bahasa Indonesia, except that the ones with Latin symbols are also pronounced with their Latin names. For example, sodium is called natrium in Indonesia and potassium is kalium. The only chemical I had to learn was copper, which is common enough that an Indonesian word exists for it: tembago. I labeled the solutions A, B, C, and D and told the students that they would have to observe the colors in the flame, then make their best guess as to which chemical each solution was. It took some doing and many dips. The copper kept contaminating the results for subsequent chemicals, but the potassium was good and the sodium simply made the orange flame oranger.

Flame test lab

Students in the chemistry class at SMAN 1 Mandastana conducting a flame test lab. I had to improvise for materials and chemicals, but the lab turned our fairly well. It was a true challenge in global education!

When we finished, I had the students shout out which solution they thought each was, and they got it right. I understood the names of the elements in Bahasa Indonesia by this time, so I didn’t need as much translation. Barium had to be guessed by a process of elimination. Given the challenges of the materials and the alcohol lamps, which simply didn’t get hot enough to really see the colors well, this lab turned out quite well. I will never forget this experience of teaching a science lab in a foreign language using scrounged materials.

As I observed the chemistry teacher the day before, and as I taught this class, I was struck by how impossible this would have been if this had been any subject except science. Yes, Nazar helped translate, but I was able to use Indonesian words for the elements and explain a few things where he didn’t know the words, since he is an English teacher and not a science teacher. Where Nazar couldn’t translate and I didn’t know how to explain, the chemistry teacher and her assistant were able to. Science is truly a universal language, but I have never put it to the test like this before. I was even able to do some explanation of quantum leaps and color emission, which the students seemed to understand. I don’t know if they have studied this before, but I saw comprehension on their faces despite some fumbling with the translations, more so than I usually see in American students’ faces.

Flame test

Looking for the blue flame of copper (tembago) sulfate.

Nazar said we could treat him to American food today, so we drove back to the city. We passed a large mosque at a roundabout that we had stopped at on Sunday in order to say prayers and use the restroom, but now there was a protest going on in front of the mosque in the traffic circle itself. The signs said this was a protest in favor of Palestinians in Israel. We didn’t stop, as we had been told not to get to close to protests as the mood of the crowd can turn ugly fast. This protest seemed pretty peaceful, with a few banners and people chanting but nothing else.

PE class with Nazar and Craig

Before the chemistry class, we went out with some of the students during their PE class to visit the junior high school next door and to see the area. Notice that the students are walking (and running) on a rough road surface in bare feet. The girls wear PE hijabs which seem very hot to me to wear in this heat.

We found a Kentucky Fried Chicken place near the Duta Mall in Banjarmasin. It was fairly standard KFC, except for the steamed rice they served. You can’t get away from that. But I think I’ve had about enough fried chicken for a while. I was running short of money, so we found a currency exchange place not far from the hotel and I exchanged the rest of my U.S. dollars (about $60) into rupiah, which was quite a pile.

Interesting name for a store

We passed this store on our way to the school, and I got a photo of it this morning. It is the old logo of my college alma mater, a strange thing to see in Borneo.

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Schrodinger illustration

Erwin Schrodinger

My students will tell you that I am a massive Star Trek fan; in fact, I have most of the episodes of all of the series on VHS tapes or DVDs. A number of years ago, an episode of The Next Generation featured Data trying to learn what humor is. He went to the holodeck and asked the computer who the funniest stand-up comedian of all time was, and got the answer that it was a 21st century comedian whose subject was quantum mechanics.

This intrigued me. Could one actually make a good stand-up routine about quantum mechanics? While teaching at Provo Canyon School, my students weren’t able to do most standard chemistry labs due to the circumstances, so I taught a course that was more theoretical. For an extra credit question on our test on quantum mechanics and atomic physics, I asked them to come up with a joke or pun that involved terms and ideas from these subjects. The students took more time on that one question than all the rest of the test combined, and the results eventually mutated into a stand-up routine by a cartoon character called Boson the Clown. I’ve described him in a previous post (The Atomic Comic Club).

This last week, my chemistry students came to their test on the same subjects and I asked the same question. Here are samples of their jokes:

So Heisenberg was driving one day when he was pulled over by the police. The officer asked him, “Sir, do you know how fast you were going?” Heisenberg replied, “No, but I know where I am!”

There were three men named Mark, Larry, and Alphonso who were at a wrestling match. The match was between Mark’s grandma and a rabid grizzly bear. All the odds were against her and she was feeling rather down. Mark was trying to cheer her up while Larry took bets outside. Suddenly, Larry burst into the room yelling, “Alpha’s  beta on your Gamma!”

 

 

Fractal image of p and s orbitals

Fractal image similar to p and s-orbitals

 

Why did the electron cross the road? He never did – because he was quantized, he was already on both sides at once but never in the road.

There was a cat named Schrödinger;
In a box is where he hid.
When poisoned with lead,
Old Erwin said,
“The cat is both alive and dead!”

 

The vet at the particle zoo had a problem with beryllium. He only had two options – to curium or to barium. He had a dentist to boron the beryllium’s tooth. I’d give a nickel to see what happened when the beryllium woke up; now the vet and the dentist argon.

Did one particle in the particle accelerator like the other? Yes, they had a “smashing” good time!

 

 

 

Fractal image of f-orbital

Fractal image similar to the shape of an f-orbital

 

An electron walks into a bar and the bartender says, “Why so negative?” The electron says, “My girlfriend just met this photon and moved out on me.” The bartender says, “Well, that’s too bad. But do you see that young particle over there? She’s dying to interact with you.” The electron thinks, “Maybe this is my lucky day!” and swaggers over to meet her. He asks her name. “Positron,” she says. “Nice to meet you!” he says and shakes her hand. Boom! It was annihilating love at first sight. Now they have a bunch of baby quarks.

A boson checks into a hotel in Neutrino City. He asks the neutrino at the front desk how much it costs to attend services at the local religious shrine. The neutrino replies, “There’s no charge, but I’m afraid we don’t offer mass.”

Some of them are actually pretty good as jokes and even better as evidence of an understanding of atomic physics.

We are now studying quantum mechanics and I have prepared a Keynote/Powerpoint presentation on quantum numbers and electron configurations. I am including it here in case anyone out there could use it; please feel free to make use of it however you like, just give me credit (consider this to have a Creative Commons 3.0 Attribution Only license).

Powerpoint File: Quantum_Numbers

PDF File: Quantum_Numbers

Standing waves at Goat Island

Standing waves near Goat Island, Hawaii

I’m struck, as always, by our inability as humans to adequately visualize subatomic properties. We think of these “objects” inside the atom as either being particles (like small, hard balls) or as waves, constantly in motion. Our models are the solar system of planets orbiting in nearly circular orbits around the Sun, and waves of water in the ocean producing a nice sin wave pattern as they wash up on a beach. It turns out both of these models are partially true; subatomic particles sometimes behave as particles (as in Einstein’s paper on the photoelectric effect) and sometimes as waves (such as Louis de Broglie’s experiments). The truth is, subatomic particles are really neither of these things – they are what they are, but we have a hard time coming up with models that describe them well. On the other hand, the quantum mechanical equations of Schrödinger, Heisenberg, and others describe the electrons so perfectly that we can create such amazing devices as Magnetic Resonance Imagers and iPads. The mathematics is very accurate; our visual models are the only things that need work.

I like to think of electrons as standing wave patterns. The example I give my students is the waves near Goat Island, Hawaii. This is a small island located just off shore to the northeast of Oahu. As waves break around the island, they are bent in two directions as they pass between the islands, coming in at about 90 degree angles. As they meet, the crests of the waves reinforce each other to create large humps at regular intervals. These are standing waves that slowly move toward shore. You can actually float on top of them and ride them for a few seconds. Between these humps, there are no waves at all and the water is very calm where the waves interfere with each other and cancel each other out.

Waves near Goat Island

Waves bending around Goat Island

According to the quantum numbers, electrons are standing waves as well with only certain energy combinations that are stable (where the waves add up). This is why the principle quantum number n is always a positive integer; any non-integer solution tends to cancel itself out, like a wavelength of 3.5 bent around the nucleus would completely interfere with itself. This is why Planck saw the quanta as being fixed energy levels where electrons could be found, but never in between.

Frozen energy s-orbitals

The s-orbital electrons create a spherical shape based on probability

Another way of looking at subatomic particles (and all matter for that matter) is that they are crystallized or frozen energy; chaotic energy patterns are trapped in a lattice or matrix of quantum numbers. I am again reminded of the patterns I see in fractal math or chaotic geometry. The atoms freeze the energy patterns, but using particle accelerators, we force the particles into phase transitions and release the trapped energy, which soon re-freezes into other particles. The more energy we can add through our collider, the more massive the subsequent collision debris will be. The dance of energy at the heart of matter is elegant and beautiful.

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