Sunday, December 26, 2010

Cold Mountain

Anyone out there seen Cold Mountain? I love the movie. Back when I was a beach dweller here in San Diego I used to take walks down to the Blockbuster on Mission Ave. and purchase old VHS tapes they kept outside on a table for 2$. Lucky for me they were purging their supply back when I lived there. I have some gems on VHS (and a good thing I still own a VHS player!) (including Cold Mountain)

I tutor at the library and happened upon the Friends of the Library collection near the front door. What a deal! People donate paperback novels- everything from Garrison Keillor to Phillip Roth and Dan Brown....and Cold Mountain. Whatever is on the shelf is fair game for 50 cents. Yes, that's 50 cents. What a deal. For this reason I have my own copy of Cold Mountain. (I also own books I would never buy at the store price: Kite Runner, Memoirs of a Geisha, Devil Wears Prada, two Keillor novels, and Schindler's list just to name a few). If you've never checked out your local library for the cheap paperback (used) books then I would go take a look. I've never had such cheap, yet quality entertainment. In this case that is definitely not an oxymoron.

I digress but I return to the purpose of this post. Cold Mountain. What a powerful novel. Superficially it is a touching romance. The movie emphasizes the romance and the scenery. There is a bit of information about the war but really not much more than what you might learn from Gone with the Wind. The Civil War was initially portrayed as a romantic, exciting and noble cause for the good of the south. So different from what it ended up becoming at the end of the war- a blood bath of meaningless massacre and heartrenching horror. As also shown in Gone with the Wind many southerners became scavengers and hunters as their currency lost value and people's possessions were diminished by poverty and raids by home guard and invading soldiers.

Cold Mountain goes into a bit more detail than other civil war books about specifics of battles and cultural implications of melding the north with the south. I wonder how accurate some of the information really is. For example, one of the concerns of the southerners was that they would have to acquire an odd holiday from the north called Thanksgiving. Imagine dedicating one entire day just to giving thanks- I mean really, what a silly idea. Hard to believe this was a mockery amongst gentry of the south during the civil war.

The author is a genius in flashback techniques. The story is mostly told in retrospect as stories within the main story. Inman (the main male character) has been badly injured in battle and deserted his recovery process in an army hospital. In the chapters that focus on him he is wandering through the wilderness trying to find his way back to Cold Mountain. On the way he meets many different types of folks, some helpful and some hurtful. He also recounts his relationship before the war with Ada Monroe on Cold Mountain- the woman he is hoping to meet again alive in Cold Mountain.

While Inman wanders in the wilderness the chapters intersperse themselves with the account of Ada Monroe back in Cold Mountain. At the beginning Ada is a half-starved, desperate and abandoned daughter of a missionary father. His death left her near penniless and without skills to survive on their farm at Black Cove on Cold Mountain. Slowly, however, through the help of neighbors and a crass, abandoned uneducated farm hand named Ruby she gains a knowledge of growing her own food, tending livestock, and growing into self-sufficiency on her farm. Previous to this experience her skills were nothing that could actually be rendered useful: arranging cut flowers, playing the piano, reading novels.

All this survival on both sides is for one goal: reuniting the love between Ada and Inman. Slowly in the evolution of Inman's wandering and Ada's increased self-sufficiency we learn of a long-lost love discovered during a different time. A time before the war when gentleman existed in the south and integrity and honor reigned in the grand old south.

The scenery throughout the entire book is extremely touching. I really want to go to North Carolina to see Cold Mountain in real life. Apparently it is a real place.

I am enthralled by the writing and the plotline. The author draws us into a rather unusual romance between an ordinary farm boy and a woman of social standing. Then, we are drawn even more into the forces that pull them back together after they are separated. Inman nearly dies several times during his journey back and each time he scrapes by it seems that his desire to see and reunite with Ada drives his will and wit to pull through. It is love that truly saves the day in the end. Inman survives and arrives back home.

I won't reveal the rest of the ending. It is fascinating. I recommend a read of the book.

Wednesday, December 22, 2010

A Jane Austen stage perhaps?

Its really interesting that Jane Austen's novels have eluded me thus far. I say that because I have heard about her and her writing in several situations and even watched a few of the Hollywood-interpretation movies since the '90s. It seems like the kind of movie that would grab me, doesn't it? An Anne of Green Gables or Laura Ingals Wilder turned adult romantic and an old-fashioned, harmless, complex exploration of relationships and their meaning. When I was in college, my favorite professor handed out a list of books she considered for our lit class. At least three of Austen's novels were on that list. I still have that list in a manila folder in my garage. And yet I've never picked up a single Austen novel.

But now.... but now I truly am inspired. On our flight from San Diego to Toronto I watched The Jane Austen Book Club. What an inspiration to read all of the Austen novels! About five women and one (lone) man meet once a month to discuss all of Jane Austen's novels. The themes of romantic relationships they discuss are so real they manifest themselves in their real-life relationships. It is truly touching.  And the really cool part of it is that there doesn't seem to be just one interpretation of the themes in a single book. I'm really intrigued by it. How can each person see the characters so differently?

So today in my lazy, pre-Christmas preparations (almost complete) I spent some time updating my wish list. I now have the complete novel set along with a complete movie set on my wish list. I actually chose to select the older versions of the Austen films for a very specific reason. Movies are only worthwhile if the content closely follows that of the text. According to the reviews the modern Hollywood renditions of the movie really don't treat the original plots of the novels fairly. Apparently some of the acting is spotty as well.

So here I am- yet to be made a Jane Austen fanatic.  They'll make a Brit out of me yet. So far I'm still pining away after LM Montgomery but maybe this is the bait to transfer my drooling affections to Austen. We shall just have to see.

Saturday, December 18, 2010

My current wish-list of ambition

I always have a stack of books next to my bed that fit into this category: "I should really read this book to become a more educated scientist and a better teacher." The problem with the books in this category is that by the time I come home from work after a tough day the last thing I want to do is pleasure reading about chemistry. I'd rather pick up Narnia or Cold Mountain or even Schindler's List (as depressing as it seems) for crying out loud.

But, just today I received something that really piqued my interest in terms of thrilling science. It is called the Disappearing Spoon. Yes, thrills chills, it is a book of anecdotal information about the periodic table and the elements on it. It tells tales of poison, politics and even a bit of science mixed in. I haven't read it yet but the introduction talked about mercury and its haunting tendencies to poison and hurt people.
When I first read the summary I thought to myself, "this sounds like another rendition of Primo Levi and the Periodic Table." Primo Levi is the Jewish freelance chemist who wrote about his experiences in chemistry during world war II by focusing each chapter of his book on one particular experience. The experience was somehow tied into one of the elements on the periodic table- either peripherially or focally.  I can already see that this book is vastly different from Levi's. For one thing the author is not a bench scientist. And for another he is not telling personal experiences- he is recounting facts he learned about elements mixed in with some of his own impressions and conversations with professors during his science education experience. So far it is not evident that he has been employed in science beyond his basic education level.

So- as soon as I gather lots of riveting poisoner stories and other scandalous tidbits to shock my students with perhaps I will gain ambition to read the other two books on my ambition checklist. They are these two books:
One is based on history of science classes taught at Johns Hopkins and the other is a book written by a man exploring the nature of ocean waves with his daughter. Two very different books but both potentially helpful in getting nonscientists interested in science.

I just can't muster up the ambition to actually read these books.

Narnia: a holiday treat

I never thought of myself as a particularly enthusiastic  Narnia fan. When the movie came out five years ago I chuckled, enjoyed it and mentioned to John I wouldn't mind rereading "Lion, Witch and Wardrobe" as I had done in my childhood. Little did I know this would become my most treasured holiday gift!
At Christmas in 2005 I received the boxed set of all seven books. You'll remember that in 2005 John and I were first dating and didn't know each other all that well. I guess he took my admiration for the Narnia series more seriously than I did. I never expected (nor did I really want) all seven books. But, boy was this a lucky mistake.
Now, five years later I've just finished the fifth book in the series and am thoroughly excited and anticipating the movie. Voyage is by far the best book in the series. The allegorical similarity to the Bible is so striking it touched me on a very deep level and made me read with fascination of not wanting to put the book down.
As the children and the ship move through the islands surrounding Narnia looking for their lost Lords, they experience events that closely parallel the Bible. Now, I'm not one to believe everything I hear or jump on the bandwagon but I have to say this: If Francis Collins, head of NIH (currently) can have faith without empirical evidence to back it up then so can I. Period. So I digress back to my point.
There is a section where a particularly disagreeable character turns into a dragon by his own greediness only to be transformed in character through suffering until Aslan converts him back into a human again. He is a new person in character.There is a section where Lucy uses magic to remove a spell placed on a group of people who have become invisible. This section is rather like  Harry Potter meets Disney or Harry Potter goes to church section. It explores the fantasy of magic combined with underlying themes of how emotions like fear are handled. The whole issue of fear is explored on a deep level: does fear hold us back from doing things that are really not all that daunting? What is fear and how does it control us? It is fear that nearly prevents Lucy and friends from intervening here- only to find out that it was fear itself that was the worst danger in this situation.
My favorite part is exploration of the end of the world. In this part there is an image of the lion laying down with the lamb (Biblical prophecy) and then the ocean turning into a sea of lilies. And along the way a discovery of a whole people group living underwater like humans. The whole notion of the unknown is  powerfully explored with their discovery of the uniqueness of the environment.  Nothing seems to work the way it does in Narnia or on earth for that matter.  And then at the end Reepicheep takes his own individual boat by himself to explore the absolute ends of the earth while Lucy, Edmond and Eustace suddenly find themselves back at his aunt's house on the floor of the living room.
CS Lewis is such a treat. I'm growing to appreciate him more and more. Perhaps I'll reread Dawn Treader when I have time.

Thursday, December 16, 2010

Another semester is over....

Well, another semester has come and gone and I have lived to tell about it. Seems like the exact same thing happened last semester: finals occur and then grading is finished and then I have to submit final grades. And someone is always unhappy. And I've found my unhappies already.

I heard this myself when I was a student but I don't think I really like it or believed it. "Its not the grade that matters." Over time I've grown to understand what this really means.

When I look at a chemistry text now I understand it in a much deeper way than when I was a student. I can cross-reference diagrams and find topics explained from different angles in different chapters. I never would have been able to do this as an undergraduate. It all came from years of experience and practice.

So the problem then is this: should we be coddling and comforting learners as they wade through the details of problem solving and reading the text by padding grades along the way? I don't know- I think in some ways it motivates people to give them positive feedback and encouragement. However, it certainly doesn't give them the real picture of their depth of understanding of the material. And- I'm not sure it accurately predicts how well they will perform in a more complex class (upper level)

I just gave a very hard final. I had students who normally get A grades fail the test. It was that hard. I took the questions primarily from the textbook test bank on a CD from the publisher. These are TOUGH questions. Most of them include answers that would seem logical if you don't understand the question on a very deep level. Of course, that wasn't the correct answer- only to be found through a detailed understanding of the calculations and logic behind each question. The test gave me some information about my students, however.

This test showed me which students really worked at understanding not only the math of chemistry but the conceptual grasp of big topics. One of the questions had them rank the boiling points of several compounds including covalent and ionic compounds. They were supposed to surmise that the strongest intermolecular forces and the strongest bonds lead to the highest boiling point. (The ionic compound always has the highest boiling point for this reason)  Even my best student missed this question. I'm trying to figure out how he missed this among many other more difficult conceptual problems on the test. I think it is because when we study covalent compounds I emphasize how hydrogen bonding is the strongest intermolecular force and causes the highest boiling point. What I usually don't emphasize here is that hydrogen bonding wouldn't create as high of a boiling point as ionic bonding.  So- for covalently bonded compounds ONLY,  hydrogen bonding would cause the greatest elevation of boiling point. Ionic compounds are in a whole different class altogether.

I hope my students take the experience of this excruciatingly difficult test as a motivating learning experience. This is but the first of many tough exams to come in their scientific or medical careers. It will prepare them to really study and think and examine what is important. It also teaches them there is no free ride. School is hard work.

I'll post this exam with the answers for my students next semester to chew on all semester. I plan to make the final more straighforward (with any luck I'll succeed- I had no idea this test would be this hard) I'm hoping that by chewing on the questions from this test students will be prepared to ask themselves and answer the really tough conceptual material.

Chemistry is no cake walk.

Tuesday, December 07, 2010

Arsenic in DNA?

Arsenic Article
I just read an article in the Wall Street Journal about Arsenic in DNA. This is profound, if true, and a bit scary.

Arsenic? A  poison? Found incorporated in the genetic code of life. I was shocked. Researchers are suggesting this is new evidence that there is life outside of planet earth. This may redefine the essential elements of life.

Sunday, November 14, 2010

Why is water a liquid at room temperature?

Have you ever wondered why there is nothing else like water on the planet? Many compounds have similar molecular masses: oxygen, nitrogen, sulfur, etc, etc, etc. Water is the only compound in its molecular weight class that is a liquid at room temperature. Why is it so unique?

It is because of forces between molecules called hydrogen bonds. The hydrogen atoms of one water molecule are attracted to the lone pairs of electrons on the oxygen atoms of adjoining water molecules. This attractive force between molecules is very, very weak on one hand; compared to the attractive forces of a chemical bond, the hydrogen bond attractive forces are really small. Over large distances, however, these small attractive forces add into something very, very powerful. An overall sticky effect is created. "Sticky" in that the water molecules are more attracted to each other than molecules of that molecular mass would normally be. Molecules like oxygen gas and nitrogen gas are gases at room temperature. Because of the hydrogen bonding between water molecules, water is a liquid at room temperature.

Because of hydrogen bonds we have lakes and streams. We have capillary action that allows water to climb the trunks of trees to the branches, we have snowflakes, icicles, and icebergs that float on the top of oceans.

Water is amazing.

Tuesday, November 09, 2010


This ubiquitous equation is known throughout the world.
People use it as a password to their website, and as a button slogan. I think my high school chemistry teacher made us write it on stickers and put them on our foreheads..... (oh dear)

The ideal gas equation summarizes the discoveries about the behavior of gases into one neat and tiny equation. Let's start with the left side:

This is Boyle. Boyle's law states that the pressure increases as the volume decreases. This is known in science as an inverse relationship: P ~ 1/V.  The best illustration of this is scuba diving. When a scuba diver goes down into the depths of the ocean the pressure increases. (Makes sense when you think of tons and tons of water weighing down on the ocean floor). As the pressure increases, the volume of the diver's lungs decreases. As the scuba diver rises to the surface, the pressure slowly decreases and the lungs can expand again. When a diver gets "the bends" the person swam upward too quickly and did not allow  pressure/volume equilibration to relieve excess pressure. A scuba diver's lungs can actually explode in such a situation. (Like removing the lid on something tightly compressed in a jar- it springs out)

The left side is equal to nRT. Charles's law told us that volume and temperature are directly proportional: as temperature increases, volume increases. Think about the amount of space something takes up when it is moving slowly versus the amount of space it would take moving quickly. This is why you can get a half-filled balloon to perk up by warming it with a hair dryer. The partially filled balloon seems to suddenly have more air (even though it doesn't) when the particles start moving faster.

We also know P ~ T (direct proportionality). Think about the pressure exerted by air in a balloon. Does it exert more or less pressure at room temperature or when heated with a hair dryer? As the hair dryer heats up the molecules inside they move faster and increase their volume. In the process they exert a higher and higher pressure on the walls of the balloon.

The joys of lecturing.....Today is PV=nRT

Wednesday, November 03, 2010

Why we can survive carbon monoxide poisoning..... ( read to the end)

My students have been drawing Lewis dot diagrams and predicting shapes of molecules based on their Lewis dot structures. This is a very detailed process and requires them to be familiar with the concepts of valence electrons, types of bonds and bond orders. It is so easy to get lost in all the details. This is why I wanted to stress the importance of WHY. Why does anybody really care about the shapes of molecules. Does it really matter?

Saturday, October 30, 2010

Ionic and Covalent Bonding

This week my students did the molecular model lab which is a bummer for them because we are one class period behind in lecture. So- if they didn't take the time to really read chapter 8 thoroughly before lab (most of them probably didn't) then the lab probably went in one ear and out the other.

I'm not sure if it makes more sense to try to explain ionic vs covalent bonding before or after Lewis structures/VSEPR shapes. By learning to use the Lewis Dot model students can predict shapes which influence the overall bonding characteristics of molecules. The larger concepts of ionic vs covalent bonding can be explained without knowledge of Lewis structures, however, the details seem much clearer once the model is explained.

Stay tuned for my upcoming post on ionic vs covalent bonding...

Can't wait!

Thursday, October 28, 2010

Friends of the Library

If you have never gone to your local library to look at the paperback books donated to Friends of the Library charity you are missing so, so much. Since I discovered this gold mine of entertainment I have ransacked its shelves with my eyeballs. I have enough restraint not to ransack it with my hands. My most recent comparison to my love of books is my love of food. I eat books like I eat food. It is a hunger to be fed daily.

Today I found Middlesex (Pulitzer Prize winner), The Spirit Catches You and You Fall Down, and The Castle by Kafka. I think perhaps the Kafka and Middlesex usurp the ranking of books on my list. Middlesex is next after I finish The Wednesday Sisters.

I intended to buy Middlemarch (as opposed to Middlesex) because The Wednesday Sisters recommended it but I have too many books in line.

Each paperback is 50 cents. Sure beats spending $15 on

Wednesday, October 27, 2010

Periodic Trends on the Periodic Table

In class yesterday we covered the electronic structure of an atom. We Primarily focused on electron configurations and orbital diagrams (and many did very well on the simple quiz I gave midway through the period). Near the end of class I briefly talked about periodic trends, the topic I want to focus on in this blog post.

In our discussion about the periodic table we talked about how each period represents a primary energy level within an atom. Period one is the energy level closest to the nucleus while period 2,3,4, etc are further and further from the nucleus. We also talked about how each period represents a fixed energy level. This returns us back to the concepts of electromagnetic radiation we covered earlier in the chapter. Fixed energy levels were first observed in heat radiating from everyday objects. The energy levels of the measured heat were discontinuous. This same observation holds true for electrons surrounding the nucleus of an atom.

Wednesday, October 20, 2010

Quotation from JD Salinger in Short Story

A break from science for a minute......

My other love in life is literature. I'm reading Nine Short Stories by JD Salinger. Here is a quotation I'd like to share:

"This is the squalid, or moving part of the story, and the scene changes. The people change, too. I'm still around, but from here on in, for reasons I'm not at liberty to disclose, I've disguised myself so cunningly that even the cleverest reader will fail to recognize me."

He turns out to be the main character of the second half. But you don't figure it out until near the end. Genius.

chemicals in everyday items (potentially harmful)

There is an article in the Wall Street Journal on Monday that caught my eye. Actually the entire Personal Journal section caught my interest: emphasis on green energy. Since I teach alternative energy sources in my class this section was an opportunity for me to update my knowledge on the subject.

The article (click on link for article) has a list of chemicals in a table with the corresponding product in which they are found. I'm going to go check out my personal food containers after reading this article because apparently I have to watch out for dibutyl phthalate.

This brings me full circle to my concerns about sulfuryl fluoride (not mentioned in the article) that is used for termite tenting. As a chemist I know that both sulfur and fluorine have some nasty properties as individual elements. And- the fact that the compound is used to kill termites means it is toxic on some level. Will it end up on a list like this one twenty years from now? In the future will we talk about termite tenting and the harm it caused like we talk about the babies harmed by Thalidomide in the 70s? Or even asbestos? It's really scary to me.

I'm getting tented in December and I'm worried about it.

Tuesday, October 19, 2010

Understanding as "acceptance" rather than related on a deep level

I touched on this below but I wanted to revisit this idea. Often learning the crux of a subject is more about acceptance rather than true understanding. How can you really understand something if you are new? On the level of an introductory course I think this concept applies to other subjects: art, religion, English and even History (to some extent).

I like to think of my students (that may be you if you are my student) as doing practice problems and reading the material in the textbook so that they grasp enough of the details to accept what the experimental evidence tells us about the way chemical elements behave. None of it is intuitive and none of it is something I would expect anybody to figure out without explicit information from the text.

I hope everybody out there who is currently studying chemistry can grow in their acceptance of experimental data. It is only through this acceptance that you can understand more about how the experimental evidence may affect medicine, physics and the everyday way we live our lives.

I'm sure the founders of quantum mechanics had no idea that they had just unleashed the beginning of the information age. The internet and all the small gadgets we take for granted resulted from the acceptance and further creativity of those who observed quantum mechanics in nature.

It is my hope you will be enthusiastic to do the same. Let me be the proud teacher of the next United States inventor. Good luck.

Monday, October 18, 2010


An old friend of mine from childhood recently visited this blog and told me that he needed to take my class to understand my blog posts.

Agggghhhhhh! Bad. This is exactly what he should NOT say. Poor guy- he probably had no idea how badly I felt about this comment. I think he meant to compliment me.

The idea is to make science understandable to any soul who happens to find themself on my blog. I want people to find the posts generally interesting and students to find them a good introduction to the meatier and drier textbook.

preparing to teach the structure of the atom....

I'm preparing to meet with some students at SDSU who are enrolled in chem 200. I taught the lab for this class back in 2000-2002 so I'm familiar with the textbook and general setup of the class. Actually, I'm using the old text I used as a TA! They are now on the 5th or 6th edition of the book and I'm using the 2nd. (Hint for those of you wondering if you need to buy the next edition every time it comes out)

The concepts I'm preparing for my 200 students are very similar to those I'm preparing for my chem 3 students up in Irvine. We're beginning our study of atomic structure mostly focused around how electrons move in orbitals around the nucleus of an atom. It is these trends that determine most of the trends in how elements behave on the periodic table. If a student understands electronic structure, that student will make more accurate predictions about chemical behavior of different elements.

The first step to really understanding atomic structure is to realize that nothing that is observed in intuitive. To that end I would like to describe the study of atomic structure less as "understanding" and more as "acceptance" about what is observed by experiment. It is too bad we cannot invest in laboratory equipment to demonstrate atomic structure by experiment to all students. Unfortunately, the cost and convenience of doing such is entirely unrealistic and we must resort to explaining what scientists observe when they run these types of experiments. After reading several different ways that atomic structure affects trends in the PT, students will begin to see patterns, learn vocabulary and grow to accept experimental observations. Ideally, they will be able to use this acceptance (rather than "understanding") to make educated guesses about how other trends might function.

But- it's all tied into an understanding of electromagnetic radiation as well. The energy of electrons and how energy is distributed in chemical reactions is done through electromagnetic radiation. This is why there is an entire section about how our understanding of light and energy has changed over the years.

This is a fascinating subject to learn but I must admit, there is a certain amount of drilling and memorization that must accompany your first attempt to learn it. You will encounter concepts, observations and ideas that are completely foreign to you. I recommend whipping out those flashcards that you used to learn the polyatomic ions and using them to drill yourself about the basics of atomic structure.

Saturday, October 16, 2010

electromagnetic radiation and chemistry education

The concept of electromagnetic radiation introduces us to the idea that things are not the way we perceive them. This concept applies to more than just e-radiation in life. It is an excellent example of how we should think about other things in life that seem so, so clear. Maybe they really aren't so clear after all.

We see sunlight as white light that allows us to use our eyes during the day and forces us to turn on a floorlamp or flashlight at night. From the gorgeous rainbows left after a storm we know that sunlight can be broken up into different colors.

The makeup of sunlight seems fairly straightforward-logically it would be a wavelength travelling super, duper fast from the sun. If you extend this idea behind what we can see with our eyes, there is an entire spectrum of wavelengths emitted from varying sources (other than just the sun) that serve different purposes. From radio waves (extremely low energy) to cancer-treating gamma rays (extremely high energy) the electromagnetic spectrum has propelled technology in our lives to a level previous thought unattainable.

The seemingly straightforward makeup of white light and other electromagnetic radiation is not so straightforward. The study of this medium led to Einstein's Nobel Prize for the photoelectric effect (light as a wavelength and a particle) and to other phenomena of quantum mechanics. The subatomic processes of light are so different from what we experience in the macroscopic world that it would take an entire degree of classes to really wrap your mind around it. 

If you haven't ever goggled the electromagnetic spectrum, I suggest you google it. Do some background reading on a basic science concept that has revolutionized our lives.

Tuesday, October 12, 2010

Review for Chapters 4-6

The Exam is a week from Thursday and I suggest you start reviewing now. I am in the process of checking with some other faculty about posting the pdf of complete solutions for the problems in the back of each chapter. Someone brought it to my attention that the solutions manual in the library only works out the solutions to the odd numbered problems. I would like to post a solutions manual (as pdf) that works out both even and odd numbered problems. Please be patient as I verify that I am allowed to do this.

Friday, October 08, 2010

Quotation from the Periodic Table by Primo Levi

I just finished The Periodic Table by Primo Levi. Here is a quotation that jumped right off the page at me.

"Our atom of carbon enters the leaf, colliding with other innumerable (but here useless) molecules of nitrogen and oxygen. It adheres to a large and complicated molecule that activates it, and simultaneously receives the decisive message from the sky, in the flashing form of a packet of solar light; in an instant, like an insect caught by a spider, it is separated from its oxygen, combined with hydrogen and (one thinks) phosphous, and finally inserted in a chain, whether long or short does not matter, but it is the chain of life. All this happens swiftly, in silence, at the temperature and pressure of the atmosphere, and gratis: dear colleagues, when we learn to do likewise we will be sicut Deus, and we will have also solved the problem of hunger in the world."

Photosynthesis made beautiful- don't you think? Primo Levi is a genius of a science writer. I'll have to go back and read his accounts of his days at Auschwitz and other experiences.

Saturday, October 02, 2010

Chapter 6 Preview

As I read and prepare chapter 6 (the students are the not the only people responsible for preparing the material) I am reminded that this chapter is really critical to a fundamental understanding of beginning chemistry. Here is why:

You learn how to balance equations in chapter 5. Fair enough. You learn that the relationship between number of molecules on each side of an equation is also equal to the number of moles of each compound on each side of the equation. Let's review a simple example:  O2(g)  +  2H2(g)  = 2H2O
Let's add atoms on each side of the reaction: 2 atoms O and 4 atoms H on the left while there are 2 atoms O and 4 atoms H on the right side of the equation. It is balanced. What does this mean exactly?
For every one molecule of oxygen gas you must have 2 molecules of hydrogen gas to get 2 molecules of water. Can you get less than two molecules of water? No- because you can't cut a molecule in half. Likewise, you must have one mole of oxygen gas for two moles of hydrogen gas to get two moles of water. The relationships, as you can see, between molecules of compounds and moles of compounds are equal.

This is what enables us to use these relationships in the laboratory in a practical way. From these molecule/molar relationships we can calculate the amount of product we should get in a chemical reaction. Returning to our synthesis of water example:  If we start with two moles of oxygen gas and unlimited hydrogen gas how much water should we get? The mole relationship between oxygen gas and water is needed to figure this out:( 2 moles O2) X( 2 moles H2O/1 moles O2 )= 4 moles H2O. This is the maximum yield. What if you go into the lab and determine that this reaction only yields 3 moles of H2O? Then we get into a calculation of percent yield. The percent yield is the comparison of the actual yield you obtain in the lab with the theoretical yield you calculate based on molar ratios of a balanced equation. Percent yield is as follows: actual/theoretical X 100. In this case it is 3/4 X 100 or 75%. You obtained 75% of the maximum amount of material you could get from this reaction with these amounts of reactants.

This chapter also introduces energy transformations. Just as mass is conserved (atomic theory), energy is conserved in nature. This means that energy is transformed from one form to another. This applies to chemical reactions as well as everyday objects like a ball bouncing on the ground. There are a few key terms here you should really learn well: exothermic vs endothermic.
Exothermic: This means a reaction (or process) gives off energy
Endothermic: This means a reaction (or process) absorbs energy
The diagrams for each of these are in Chapter 6. Familiarize yourself with the energy levels of products and reactants for each case.

And...... my favorite thing in chemistry is introduced. That is Calorimetry. What is calorimetry? It is the measure of the transfer of heat.
There is a very simple demonstration you can do in the classroom to show calorimetry. I haven't figured out how to incorporate it into our class- the ice would melt by the time I get to the topic in class.
You take a styrofoam cup, thermometer, and ice/water. You measure the temperature of the water initially. Then, put a  piece of ice into the water. Let the system come to equilibrium (even temp) and measure the temperature again. This is the temperature change you plug into the equation q= mC(Tf-Ti). This measures the transfer of heat from the surrounding water to the melting ice. In this case, the ice is the system and the water is the surroundings. You are measuring the heat that is being transferred from the water to melt the ice.
In the equation: q (heat transferred) = (mass of ice+cup+water)(C-specific heat of water)(Tf-Ti)
Heat transferred is equal to the mass of the entire system  X 4.184 (constant value) X change in temp.

If you understand this basic experiment it will help you understand the concept of heat transfer.

See you Tuesday.

Wednesday, September 29, 2010

Exam I Feedback for Students

I just completed the grading for exam I and I wanted to summarize my feedback here on the blog. Hopefully this will allow you to look at these issues with your textbook in hand. I will also mention them during class- we can do some examples as a class.

Overall the average was in the mid 60s but this is because there were a few really low scores that really pulled it down. There were 6 people who scored above 90%. One person got a 98%. So- it was a manageable test. I had a good number of people in the 80 range and a few in the 70s. There were also a good chunk below 70 and this concerns me. My goal is to work hard with each of you that scored in this range so you can bring up your scores. Your homework/quiz/activity grade will help you bring your score up somewhat but you need to concentrate on performance on the tests to really do well in the class (A or B grade).

Several of you still struggle with the concepts of conversion, units and volume/density. There are a few of you that only struggled with this concept- if you had answered these questions correctly you would have been above 90% on the test. So..... keep these things in mind: Zeroes that occur before the decimal place or after the decimal place but do not follow a digit that is 1-9 are not considered significant. Therefore the number 0.00347 has only 3 significant digits. The three digits preceding the "347" are not considered significant. The number 0.03470 has 4 significant digits. The last zero is considered significant because although it falls on the right of the decimal, it follows a digit that is 1-9 and is therefore considered significant. Everybody needs to keep in mind that I consider it crucial for you to show your calculations and logic in the short answer section. I CANNOT award partial credit for an incorrect answer if you do not carefully show me your mathematics progression. I wanted problem 44 and 45 to be an easy 20 points for everyone. These were the density/mass/volume conversions and the volume conversion problems. Several of you got an answer that was on the right track but you did not receive partial credit because you did not show your calculations.
Keep in mind that while a cm3 (superscript 3) is equal to a mL, it is a dm3 (superscript 3) that is equal to a Liter. There are two ways to solve this problem (convert to dm3 or just convert from mL to Liter with the conversion 1000 mL/L) Several of you need to review your basic conversion factors- I gave you a table of all of the factors but people did not use this information correctly. I had people converting cm into meters with the conversion factor 0.01cm/m. It is opposite: 100 cm/meter. Review how these are used in word problems.
I wanted people to notice how I put a problem on the test that was an example we worked in class. Actually- this problem was in both the multiple choice section and the calculation section: You were supposed to figure out the relative atomic mass of an element based on two isotopes found in nature. There were too many people who missed this problem. I was hoping you review lecture notes and examples from class so you can get these types of problems correct.

I was very pleased with the knowledge of the class about atomic theory. The last problem was supposed to be an easy 5 points for everyone. Most people got 4/5. The two modifications to Dalton in Modern Atomic Theory are as follows:  1. Discovery of neutrons allows atoms of the same element to have different masses 2. Atoms are not the smallest building blocks of nature due to the discovery of subatomic particles. (Some of you stated that H2O and H2O2 prove that the law of definite proportions is not true and this is false. The law of definite proportions just states that compounds always contain the same ratio of elements. It doesn't mean that the ratios can't vary between compounds  (which they do only in whole number values))

Problem number 10 was a commonly missed question dealing with the law of definite proportions. The ratio of sulfur to oxygen in SO3 is 32:48.  This is obtained by multiplying the atomic mass of sulfur ( 32) by 1 (for one atom of sulfur)  (from the PT) and the atomic mass of oxygen (16) by 3 (from the PT). The mass ratio of sulfur to oxygen in any sample of SO3 will always be 32:48 by the law of definite proportions.

I'll post the key and talk more about it in class.

Tuesday, September 28, 2010

The Statue of Liberty, Stoichiometry and introductory chemistry.....

(Photo taken from the Introduction to Chemistry text by Bauer, 2010)

What does the statue of liberty in New York have to do with introductory chemistry? Actually, a lot. On the most basic level, the reason it was renovated in the 80s is very related to introductory chemistry. If we want to present the reactions of the statue of liberty accurately then we must consider stoichiometry and balanced equations.

The statue had copper panels on the outside and iron used in the inner framework. Over time, the copper oxidized in air to form copper (II) hydroxide, copper (II) carbonate, and copper (II) oxide while the iron formed iron (III) oxide. This created a displacement reaction situation. Copper metal was in contact with iron (III) ions and iron in contact with copper (II) ions.  Here is where the problem got really messy:

Fe (s)  +   CuO(s)   gives  Cu(s)  +   FeO(s)  (oh how I wish I could figure out subscripts and arrows in
According to the metal activity chart is Fe more active than copper? Yes, therefore it will displace copper's position within the copper (II) oxide compound and create an iron oxide.

This displacement further exacerbated the oxidation problem. In fact it accelerated the problem by a factor of 1000 and the statue needed to be rebuilt.

See page 179 of your text for more information.

Monday, September 20, 2010

Most aspects of e-waste not regulated in U.S., Va. | Richmond Times-Dispatch

Most aspects of e-waste not regulated in U.S., Va. | Richmond Times-Dispatch

This is exactly why we need excellent chemistry education. Many of the hazards of chemicals in this waste dump are not understood. The long term decay and byproducts of waste are often not understood. It makes sense that as technology and materials change, our knowledge about them should increase. This includes not only how they function to improve our lives but how they function in their return to the ashes of the earth. "Ashes to ashes and dust to dust."  Unfortunately, in this context the route to ashes could be a problem.

Thursday, September 16, 2010

where I left off.......preparing for exam I

So anyway, let me continue.......

Dalton's atomic theory was tweaked over time (as we like to say today). He originally said that atoms were the most basic unit of nature and that it was the smallest unit of matter. This is both true and not quite true today. It is true that in a chemical reaction, the smallest unit  is an atom. We look at whole number of atoms per formula unit. You cannot have a formula unit with half of an atom of any element.  However, it is not quite true in that subatomic particles exist. The smallest unit is, I think, yet to be discovered. However, the subatomic particles we study in this class are the proton, neutron and electron which I will talk about in a minute.

The other part of Dalton's theory that needed to be tweaked was his idea that all atoms of the same element have identical mass and chemical properties. This is not true because of the notion of neutrons (of which Dalton was not aware). Neutrons alter the mass of the nucleus and the overall atom. We now treat the mass of any given element on the periodic table as a representation of the relative abundance of that element in nature. 

Protons, neutrons and electrons and why they matter.....
Protons are the crux of all chemistry because they define the identity of an element. The number of protons is like someone's last name. It identifies their characteristics. If something has 6 protons it is carbon regardless of whether or not it contains neutrons or how many neutrons it contains. The number of protons defines the type element you are dealing with: other subatomic particles dictate the variety of that particular element.

Electrons are the subatomic particle that gives flavor to the element. Is it positively or negatively charged? This will depend on the ration of protons to electrons. Naturally something with 11 protons (Na) and 10 electrons will have a 1+ charge. This is very useful to understand in terms of formulating compounds that have an overall neutral charge.  We talked a bit about how JJ Thompson discovered the electron with a cathode ray tube and then Millikin came along and measured the mass and charge of the electron with the oil drop experiment. Ultimately, it became clear that the electron was exponentially smaller than the proton/neutron.  For this reason we discount its mass when calculating mass values on the periodic table.

Neutrons are their own category of subatomic particle that provide neither overall charge nor chemical identity to an element. Neutrons influence mass value only. Remember that we performed several relative mass value calculations in class to find relative atomic mass values reported on the periodic table.

The plum pudding model of the atom was eventually debunked by Rutherford who performed the gold-foil experiment to show that the nucleus of the atom contained most of the mass of the atom surrounding by a cloud of tiny electrons.

We talked about different notation systems to show number of protons, neutrons and mass value for various elements. Know the various notation systems and be able to use them on a test.

What are isotopes? Isotopes are different forms of an element that differ only in number of neutrons. Typically radioactive isotops are found in nature in small amounts and used as tools for radiometric dating and other scientific tools.

Once you understand that the periodic table is arranged by atomic number (# of protons) and you understand where the mass value comes from you are ready to start understanding how different columns/families tend to form different ions. Groups 1,2,3 tend to form 1+, 2+, 3+ charges respectively. The anions on the right side tend to form minus charges relative to how far they are located from group 8 on the periodic table. Why? Each group wants to gain the number of electrons that is identical to the noble gases. Once that magical "octet" of electrons is formed the ion is in its most stable state.

Familiarize yourself with the names of the groups in the periodic table. Know the halogens, alkali metals, alkaline earth metals and the noble gases. Know how to determine charge of an ion based on position in the periodic table.

Know your periodic table trends. Where are the metals? Where are the nonmetals? Can you identify chemical properties just by looking at position on the periodic table?

Chapter 3:
The key to chapter 3 is knowing how to classify a compound by its general appearance. For example, can you classify the following as molecular, ionic or acid?

HBr      HCl03,      NaCl,            CuO,                     Fe2O3,            NO2
Forgive me, I haven't figured out how to get a subscript to appear as a subscript in blogger. Perhaps that element of sophistication will evolve over time.

The answers are as follows:  binary acid,   polyatomic acid,    ionic,   ionic (variable charge),   ionic (variable charge), molecular

Now you use the different categories to use rules relevant to naming in that category.
Binary Acids: Start with "hydro" and add name of anion (bromine) with "ic" on the end: hydrobromic acid
polyatomic acids: Use name of polyatomic (chlorate) with "ic" and acid. chloric acid
Ionic compound (one charge): Sodium is group I and these always form +1 charge. Name all ionic compounds with "ide" ending: sodium chloride
Ionic Compound (variable charge for transition metals): Copper (name metal) (II) oxide (name charge with roman numeral and anion with "ide")
ionic compound (variable charge): Iron (name metal) (III) [charge of metal] and then "oxide" always an "ide" ending for ionic compounds
NO2: two nonmetals make a molecular compound. Use prefixes for second element (not necessary for first) nitrogen dioxide  (It would be nitrogen monoxide with only one oxygen)

That, in a nutshell is chapter 1-3 of the text!

Braindump for Exam I: What do I need to know?

So today several people stayed late after class worried about the test next week. I'm happy to see that you care about the class so much! This is an encouraging sign to me that you are serious about your work and that you will succeed in this class!

However, the question is always more geared towards this:  "How can I possibly get an A in this class? I've studied really hard and I'm still getting 6/10 on my quizzes and I don't understand the labs...." 

To you who feel this way I sympathize. It was not long ago I felt very similarly. The encouraging part of this is that it will get better. Continue to review lecture notes, try to form study groups with each other and work as many practice problems as you can from the book. Eventually the vocabular will begin to sink in and you will see the many patterns and all of the repetition that exists in the material. It is there. You just may not be able to see it yet.

So- I am leaving for a family reunion and want to give my last review for our test on Thurs on ch 1-3. I figured this would be a great blog post not to mention a great way to recruit more traffic on my site. Not only do you get 1-2 points of extra credit for a pithy comment but you get extra exam review also! What a deal.

So the crux of chapters 1-3 goes like this: (Credit to the Introductory Chemistry text by Bauer here)

Chapter 1 is focused primarily on the definition of science, explanation of chemistry and the breakdown of matter. What is chemistry and how does it differ from other forms of academic thought? The biggest difference between science/chemistry and other forms of nonscientific thought is that science uses experimentation to test out ideas. The philosophers during the middle ages were excellent at reasoning: Plato and Socrates formulated ideas from which an entire family tree of philosophers descended, however, they never tested out any of their ideas experimentally. So- while many disciplines use logic, science is special in its use of experimentation.

The definition and classification of matter is something you should review. What is the difference between matter and energy? Can you name examples of each?

Matter is subdivided into subcategories of substance vs mixture. Substances are pure in that they always have uniform composition with the same chemical and physical properties throughout. Only elements and compounds quality as pure substances. Mixtures are more tricky. A mixture is, by definition, something that contains multiple pure substances fixed in variable proportions. So, a mixture may or may not have the same composition throughout. For this reason, a subcategory has been established that differentiates between homogeneous and heterogeneous mixtures. Homogeneous mixtures (like solutions) are the same throughout while heterogeneous mixtures have a variable composition throughout. A mixture can always be separated into its different chemical components by some type of physical separation. (Filtration, evaporation, decantation, distillation, extraction, etc.)

This brings us to the discussion of states of matter. Matter can change forms without changing chemical composition. The different physical forms of matter form different states: solid, liquid and gas. These each have specific definitions and descriptions.

Energy is the ability to do work. There are all types of energies out there but the two main kinds are kinetic and potential. Within these two subdivisions are different subtypes like chemical energy, electric energy, heat energy, thermal energy, elastic energy, and many others. It is a good exercise to imagine a moving object and label the type of energy it has in various stages of movement.

Chapter 1 also covers the scientific method. The scientific method is a way of asking questions about the physical world and implementing a system of inquiry to answer those questions. Whether you hypothesize about a potential outcome or actually formulate scientific laws and theories on well-documented data, you employ the process. Review the different terms of the scientific method and familiarize yourself with them.

Chapter 1 introduces the periodic table and the classification of metals, nonmetals and metalloids. Each category embodies some similar properties of its element type. What are these properties and which elements fit into each? How would you determine this just by looking at the periodic table?

And finally conversions, significant digits, rounding, scientific notation and the entire math toolbox in chapter 1 will be critical to your success throughout this class and in the next class, Chemistry 1A. I recommend you master the entire toolbox for maximum learning.

Chapter 2 is my personal favorite out of ch 1,2 and 3 because it delves into the history of science. I personally believe our nation would be much more scientifically savvy if our education system required everybody to study the history of science in chronology with the actual content of science classes. I actually ran into someone today who knew of a program at Harvey Mudd that tried to implement such a system. Apparently it is too time consuming for students' schedules to make it work effectively. Interesting idea, however.

Chapter 2 follows the initial idea about atoms from Democritus (Greek philosopher) in 450 BC. From here, atoms were born. Dalton formulated his atomic theory based on the ideas of Proust (law of definite proportions), Lavoisier (conservation of matter) and other information to form the four tenants of atomic theory. Note that this theory is our first exposure to a scientific theory in the chemistry text. Why is it a theory? Because it provides a broad definition of nature that incorporates scientific laws (Proust's and Lavoisier's) but it goes further to suggest something that is true of all of nature. And, like any theory it can be modified and changed as further evidence becomes available.

I will post more as another entry.

Tuesday, September 14, 2010

law of definite proportions

As I was preparing yet another lecture for my introductory chemistry class I realized something: this class is all about grasping the law of definite proportions. Once the fundamental concept of relationships in chemical quantities is realized and accepted, students can propel themselves into much bigger and sophisticated equations and chemical concepts.

What is the law of definite proportions? Let's go to my friend Wikipedia for a brief description. (I realize some readers may have an aversion to Wikipedia but I go there when my textbook is otherwise preoccupied with another instructor as it is currently.) Wikipedia is generally correct although I will admit there are some QA issues with the site.

"In chemistry, the law of definite proportions and also the elements, sometimes called Proust's Law, states that a chemical compound always contains exactly the same proportion of elements by mass. An equivalent statement is the law of constant composition, which states that all samples of a given chemical compound have the same elemental composition. For example, oxygen makes up 8/9 of the mass of any sample of pure water, while hydrogen makes up the remaining 1/9 of the mass. Along with the law of multiple proportions, the law of definite proportions forms the basis of stoichiometry."

This little paragraph nicely describes my overall definition of the law of definite proportions.

This scientific law was incorporated into Dalton's Atomic Theory in the early 1800s. Now it probably just blends in as a fundamental tenet of atomic theory, I doubt most people know it originated with Proust.

While Atomic Theory (especially modern atomic theory) is important for introductory chemistry, the class can be defined at a more fundamental level as applicable to the law of definite proportions.

Why? Here are the reasons: The law of definite proportions explains why the following are true.

1. The relationships between amu mass/molecule is the same as the number of grams in one mole of something. A strange and difficult relationship to swallow especially when it would seem experimentally impossible to prove this. I'm not really sure how they did it. (If anybody reads this and knows please fill me in)
2. The manipulation of numbers between grams, moles and particles depends on the relationships in #1 (previous bullet). Without these relationships, the theoretical yield of a chemical reaction cannot be calculated and compared with the actual experimental value. Hence, without this concept there is no percent yield calculation.
4. While the rest of atomic theory is critical to chemistry it does not fundamentally affect calculations (for which we grade the students). 
5. None of the other tenets of the theory allow for such simple yet profound manipulation of the experimental data to give predictions, results and information!

Here is the Wikipedia definition for law of multiple proportions:
If two elements form more than one compound between them, then the ratios of the masses of the second element which combine with a fixed mass of the first element will be ratios of small whole numbers.[4]
For example carbon oxide: CO and CO2, 100 grams of carbon may react with 133 grams of oxygen to produce carbon monoxide, or with 266 grams of oxygen to produce carbon dioxide. The ratio of the masses of oxygen that can react with 100 grams of carbon is 266:133 ≈ 2:1, a ratio of small whole numbers. The Law of Multiple Proportions, is just what the name suggests, the law of multiple proportions of one constant element within differing compounds sharing the same type of chemical bonding.

Last semester our learning objectives were to:
1. Calculate and predict theoretical yield in a chemical equation. Use this with experimental data to calculate percent yield.
2. Use Lewis theory to build molecules and predict shapes. Use shapes to predict molecular behavior.
3. Predict behavior of atoms based on periodic table trends

#1 is by far the most important components of this class.

Thursday, September 09, 2010

Ideas about learning: Jeanne Baxtresser and flute performance

Recently I've been listening to the former principal flute player of the New York Philharmonic on my ipod while I take a morning walk. She recorded all of the major orchestral flute solos with a commentary about each one. A virtuoso, a genius, an accomplished artist. She is all of these.

One of the solos is by Prokofiev from Peter and the Wolf. As I listened to it perpetually in awe of Ms. Baxtresser's abilities I realized something. Peter and the Wolf was my very first piano book when I was five. Newly graduated from the clapping classes of babies I had progressed into simple melodies of the treble clef. Peter and the Wolf was the introductory piano reduction my early teacher had chosen.

How is it that the difficult music demonstrated by the virtuoso Jeanne Baxtresser could also have been my initial baby food as a tiny pianist? This is the concept of levels that I'm learning in my chemistry teaching.

Everything has levels. The challenge is to find the level that relates best with the audience to whom you are addressing. In the case of flute/piano music, there is no way a five-year-old could relate to the difficult double-tonguing passages of the full-fledged Prokofiev piece. No way. However, the simple melodies are appropriate for learning how to read music. 

Perhaps I am pointing out something that is incredibly obvious. However, on some level it must not be obvious to everyone. I think this is why so many people find introductory science classes so very difficult and boring. We are not presenting students with material that they are equipped to grasp at an appropriate level. We throw Jeanne Baxtresser's virtuosity at them without ever having fed them the piano reductions that so simply and beautifully embody the melody on the five black keys of the treble clef of the piano.

For this reason, context and culture is really critical to the betterment of science in society. People must understand the concepts of chemistry and physics in terms of how it makes sense for their everyday life. After they understand it in everyday life perhaps it might motivate them to memorize chemical mechanisms, difficult vocabulary and other mundane flashcard activities. (I promote these to the hilt.)

Wednesday, August 18, 2010

acid/base equilibrium

I've taught first semester of general chemistry (or introduction to general chemistry) as a grad student and as a professor. I'm familiar with the concepts and feel very comfortable explaining these concepts. (I'm always looking for new and fresh ideas on presentation, however, so I welcome all input in this area.)

I have never actually taught second semester of general chemistry. The concepts, as I've discovered in my review, are not concepts I've dealt with in a lot of scientific detail. In graduate school, I focused on organic chemistry which is not really covered in this section other than the basics of equilibrium and the functional groups of acid/bases (and various definitions).

In my review of kinetics, equilibrium, electrochemistry and other topics, I was most struck by acid/base chemistry. So simple and yet I think this may be one of the most difficult topics covered in the entire course (first or second semester). I'm the first one to admit that one strategy in first-year chemistry is to complete many, many problems from the back of each chapter. You can practice your way into perfection and actually ace an exam without really understanding some of the larger concepts behind the problems in the book. This is especially true for acid/base behavior.
The basics of acids and bases are just that- very, very basic (haha, pun intended here). We all can relate with the sour taste of lemons (acid) or the slippery feeling of bases (milk, sodium hydroxide). This is probably the easiest lab in the book for an introductory class- you test the pH of various acids and bases and describe the characteristics of each.
On a deeper level, however, the behavior of these ubiquitous species is very, very difficult to describe chemically. You must have a certain grasp of math (mostly basic algebra), logarithms, and understand the concept of chemical equilibrium. A reaction only proceeds to the extent that the species is soluble, reactive or otherwise able to break into new chemical compounds. This is the crux of acid/base chemistry.
It is almost impossible to do the problems in the acid/base equilibrium chapter without truly understanding the concept of the dissociation behavior of an acid or base. A weak acid/base reaction vs a strong/acid strong base reaction vs a strong acid/weak base reaction all have different assumptions under which you carry out the calculations for the equilibrium constant.
Let's take a hypothetical example here: HA + OH- = H+ (superscript +) + H20
The equilibrium constant (extent to which the acid and base actually react together to form H+ and water) is written as [H20][H+]/[HA][OH-] With the assumption that H20 concentration is a constant it is removed from the equation.

So- the way the starting material is plugged into this equilibrium equation is dependent on whether or not it is a strong acid or weak acid (just to use acids as an example). For a strong acid, dissociation is nearly complete (if not totally complete) and the equilibrium of the reaction will shift toward the water/H+ product. So 1.0 moles of starting material will give 1 mole of each H+ and H20. (based on molar ratios of 1: and assuming 1 is the limiting reactant)

If the acid is weak, the equilibrium of the reaction will stay shifted toward the reactant. In this case, we use 1.0 moles of HA - X as the value of how much HA will be left at equilibrium. Because X is extremely small, HA will remain essentially at 1.0 for the purposes of the equilibrium equation. The other side of the equation will be represented by x (a very small number) in equal amounts for both products. Therefore, it will be x2 (superscript) and you have to solve a math equation (square root of both sides).

Include this in the concept of buffers and other more complicated acid/base problems and it gets really, really confusing on when you are making what assumption if you don't really understand the concept of acid/base equilibrium.

Has anybody taught this and have any advice for me on teaching it?

Tuesday, August 17, 2010

Drivin', Drivin', drivin' up to Irvine

So- next week I start teaching intro chem up in Irvine! I'm excited. Hope I can survive the commute up there.

This will give me a chance to implement some of Randall Knight's principles from his book.


Thursday, July 29, 2010

Five Easy Lessons by Randall D Knight

I'm reading a book recommended by the physics faculty at MiraCosta called "Five Easy Lessons." The ironic thing about the title is the term easy. Easy lessons? Not even close. There is nothing easy about learning or teaching physics.

This book provides many strategies and tools for student success in physics. The most poignant point is that most people learn physics by active learning instead of the traditional lecture/note-taking format.

I feel good because I implemented some of the ideas of this text last semester unknowingly and received good feedback from my students. I think someone suggested I try demos with partner discussions. I developed this into entire class periods of discussion about various slides and diagrams I put up on PowerPoint. Students broke into pairs to discuss a large question that I would propose via PowerPoint. We would convene again to discuss it as a class.
The difficult part is that I have many more things I could incorporate to increase my students' learning even more than I did last semester. There are computer tutorials, classroom automated feedback systems, flashcards and other methods of providing near-instantaneous feedback to the students. A project for the future!
The key is to provide as much feedback as possible as quickly as possible.
Not so easy, huh?

Wednesday, July 28, 2010

This morning on my walk

I took my morning walk today and listened to The Old Testament, a series of lectures by Amy-Jill Levine of Vanderbilt University. After listening to her two lectures on the northern and southern kingdoms I think I may know the chronology of historical events a bit better. If you have ever tried to read the Old Testament you know how confusing it gets in the section of the major and minor prophets. (Now I know the difference between the two and can identify them.)

What does this have to do with science in the media? Nothing really except to point out that context is important. Just as I cannot read the Old Testament straight from the text (because the language and story line just doesn't make sense to me), many of us cannot learn straight chemistry from a textbook. I can understand the sequence of events in the Old Testament if I listen to a summary of highlights from Amy-Jill Levine. And- this information helps me understand the history of the middle east, current Jewish culture and the pervading religion, Christianity, in our own society.

Many people who cannot learn chemistry or physics from a textbook (because it is dull, boring or just too confusing) might learn it better by reading newspaper articles about the applications of chemistry. Or- they might learn it by doing peer experiments and discussing the results.

Just because science in the classroom wasn't your cup of tea does not mean it is not relevant or interesting in real life.

Wednesday, July 21, 2010

A new resource for science teachers!

As a science educator, science writer and general science enthusiast I am always looking for new material that will help me explain science. The science writing community, primarily made up of journalists interested in science has been tremendously helpful in this pursuit. Today, I was reading my hardcopy of the Wall Street Journal when I happened upon a book review that rolled off the page the way coins roll out of a slot machine during a jackpot win. I won jackpot today! I have a new resource for my physics classes in the fall.

The review was about a book called "The Wave Watching Companion." The author, Gavin Pretor-Pinney explains the science of waves through analogies, real-world examples and stories. He covers electromagnetic radiation (light waves), sound waves, brain waves, mechanical waves, and ocean waves (to name a few). The book is obviously scientific in nature: it subdivides waves into their scientifically distinct types (tranverse, longitudinal and torsional). Based on the description in the review, it is geared toward the common person. He relates waves to the Tacoma Narrows Bridge, When Harry Met Sally (the scene at the ballpark when they do the stadium wave), and the way earthworms move.

I'll be curious to see how well-developed these analogies are in the book. In some cases, these books are geared at a level much higher than the general layperson. However, done effectively, the use of such analogies can make these concepts very accessible and fun for the science newbie to understand.

I was so excited about the book that I went straight to and ordered myself a copy for $12.99. Stay tune for my own review of the book. Will it meet the learning needs of my science students? We will just have to see......

Thursday, July 15, 2010

Michelle Obama's plan for obesity

I'm generally a free-market kind of gal. However, I actually think Michelle Obama is right on the money with her plan to kill obesity in America. As a nation we've proved we cannot stay fit and healthy. For this reason, we need big brother watching over us- monitoring our children's fat intake and making sure people get the exercise they need.

We all do a bit better when we know we're being watched. Maybe the government can help the watch over our children's health future.

New Financial Regulations to Hurt Farmers?

There is an article in the Wall Street Journal today that tugged at my heart. Yes, now I am living a city life in southern California. However, believe it or not, my relatives were farmers on the plains.

So- when Nebraska farmers made the front page of the Wall Street Journal I perked up and read the entire article. This article helped me understand the risks that farmers take every year when they sell their crops for money. I didn't realize the similarities of the process to stocks/investing on Wall Street. Hedging, derivatives, locking in a profit at the expense of missing a windfall of money......It looks really complicated.

I just hope that Obama and his crew are working in the best interest of these delicate souls. Their new financial bill has some changes for the way this business is conducted. They should know that the well-being of an already disappearing way of life is at stake.

I'm rooting for the small-town farmers out there all the way. You've chosen a hard life- but with some definite rewards that southern Californians miss.

Tuesday, July 13, 2010

The Psychological Effects of Eating

Bravo for researchers! I'm happy to see research delve into the greatest threat to our American life- obesity.

An article in the Wall Street Journal today called "Stomach vs Brain: Discovering Why Some People Can Resist Dessert While Others Can't" describes work being done by neuroscientists on the chemical reactions going on in the body while people eat. Specifically, they compare the chemistry of obese people while eating to the chemistry of normal-weight people. And. there is a striking difference between the two.

While you might expect a different reaction in the body chemistry of these different groups while they are actually eating, surprisingly, their bodys' chemical reactions are different if you even show them pictures of dessert foods.

One thing is for sure: Obesity is a medical condition that affects the way your brain and your entire body chemistry functions. Once you become obese you are now vulnerable to a whole new set of chemical reactions in your body that can be the beginning of the end. Moral of the story? Eat right, exercise and take care of your body.

Thursday, July 01, 2010

spurring innovation in research and development

What drives scientists to come up with new ideas? What inspires people to create, think and produce? Apparently it is NOT the structure of big pharma created in the last ten years by the merger of large companies to create mega companies. According to an article in the Wall Street Journal today the creation of these large companies has actually stifled the investigation of new products..
"Glaxo Tries Biotech Model To Spur Drug Innovations" explains how drug companies are trying to drive innovation by subdividing their research staff into smaller units. They monitor these small units by productivity with the threat of layoffs if people do not perform. It is also their hope to create financial incentives like the start-up biotechs have done in order to create immediate profit/reward for new ideas.

My question about this is whether we can really measure success of innovation by how many ideas are investigated? I would hesitate to measure success by number of products introduced. It is true that the more products you introduce the more likely you are to find one that is successful but it is also true that you can create a more effective drug by more detailed study, research, synthesis and analysis.

I applaud Glaxo for such an effort- identifying what the incentives are for performance is an effective strategy- if what they want is a higher number of drugs in the pipeline.

Friday, June 25, 2010

Absolutely Small by Michael Fayer

I'm almost halfway through this book written for laypeople about quantum mechanics. I am impressed with the clear explanations he provides for this complicated topic. He also, as he promises to do at the beginning of the book, does not use complex math to make his explanations.

The problem with this book lies in how quickly the author introduces new concepts and vocabulary and then incorporates these into his complex arguments. There is no possible way a true layperson could follow such logic. I can follow it only because I have mastered classical physics and taught some introductory quantum mechanics last semester at a JC. There is no possible way any of my students could grasp this material.

I stand firm in that quantum mechanics cannot be understood by laypeople. At least not on any deep level, that is. You must have a basic level of science knowledge before any of it really sinks in.