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Tuesday, October 21, 2014

First Day of Class

Posted by jlwile on August 25, 2014

College students sitting in class (not my class - click for credit)

College students sitting in class (not my class – click for credit)

Today was my first day teaching general chemistry at Anderson University. I promise I won’t be reporting on every class session, but I couldn’t resist talking about this one. I started the class with a little demo. Prior to class, I had soaked a Q-tip in a slightly acidic solution of phenolphthalein, an acid/base indicator. In presence of an acid, it is clear. In the presence of a base, it is pink. I used the Q-tip to write the name of the course (Chem 2110) on a large sheet of paper, and it dried clear. I soaked another Q-tip in a solution of potassium ferrocyanide (which is a light yellow color) and wrote my name on the same piece of paper, right over where I had written the course name. It also dried clear. When I set it up, then, the students saw a blank sheet of paper.

I then sprayed the paper with a very weak solution of sodium hydroxide. The base caused the phenolphthalein to turn pink, revealing the class name. It had no effect on the potassium ferrocyanide. I then sprayed the paper with a weakly acidic solution of iron (III) chloride. The acid caused the phenolphthalein to turn clear again, so the course name went away. The iron (III) chloride reacted with the potassium ferrocyanide to bring out my name in blue. I love that demo, and at least a few of the students seemed to appreciate it.

After going over the syllabus and discussing the mechanics of the course, I decided to start by giving one of the best descriptions of science I have ever heard. It comes from Dr. Henry F. Schaeffer III, the Graham Perdue Professor professor of Chemistry at the University of Georgia. He is one of the most important chemists of our time, and here is what he says about science:1

The significance and joy in my science comes in those occasional moments of discovering something new and saying to myself, ‘So that’s how God did it.’ My goal is to understand a little corner of God’s plan.

I told the students that as far as I am concerned, that’s what science is all about – figuring out how God did it and trying to understand a small piece of God’s amazing plan for His creation. I then went on to discuss the introductory material for the course.

I was pleased to find out that two of the 61 students in my class had used my high school chemistry book! I wrote that book to prepare students to study chemistry at the college level, and I have received many notes from students, parents, and teachers indicating that it has. It will be interesting to see whether or not these two students have a similar experience.

It looks like the semester is off to a good start!

REFERENCE

1. Sheler, J. L. and J.M. Schrof, “The Creation,” U.S. News & World Report (December 23, 1991), pp 56-64.
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A Chemistry Demonstration for The Atonement

Posted by jlwile on July 14, 2010

Image licensed from www.clipart.com

I have been doing the “wrap up” session for Vacation Bible School this week, and I have been using chemistry experiments to illustrate the lessons. Tonight’s lesson was about how Jesus died for our sins. It was a real challenge coming up with a chemistry experiment to illustrate The Atonement, but here’s what I did:

In a 250 mL Erlenmeyer flask, I dissolved a small amount of corn starch in 150 mL of water. I then added a small amount of potassium iodide. The result was a slightly cloudy, but mostly clear solution.

In a 50 mL beaker, I made 40 mL of a saturated solution of sodium thiosulfate.

I then filled a medicine dropper with bleach.

The Erlenmeyer flask represented a person, and the bleach in the dropper represented sin. I added a few drops of bleach to the flask, which turned blue. The color change represented the effect of sin. As I added more drops, the color got deeper.

I then showed the kids the beaker, which represented Christ. He lived a sin-free life, which is why the solution was clear. I poured the clear solution into the colored solution that was in the flask, which represented Christ coming into a person’s life. When the two solutions mixed, the deep color went away, and the result was a solution that looked like what was originally in the Erlenmeyer flask – a slightly cloudy but mostly clear solution.

WAIT! There is more to read… read on »

Entropy and Evolution, Part 1

Posted by jlwile on June 5, 2010

I was reading Dr. Hunter’s blog yesterday, and he had a post about entropy and evolution. In that post, he cited an article that comes to the right conclusion on the issue, but for the wrong reason. In fact, I am surprised that it passed peer review, since it promotes a very bad misconception regarding the Second Law of Thermodynamics. Because both creationists and evolutionists do a very poor job of applying the Second Law of Thermodynamics to the concept of origins, I thought I would try to explain the proper way to interpret the Second Law of Thermodynamics. In the next post, I will then apply the Second Law to the concept of evolution.

Before I get started, however, let me tell you the overall conclusion. The Second Law of Thermodynamics DOES NOT forbid the process of evolution. I know there are many creationists out there who claim that it does, but they are simply wrong. In addition, I know there are a lot of evolutionists out there who claim that it doesn’t, but they do so for reasons that are often wrong. So let’s talk about the Second law of Thermodynamics and how to properly apply it to many situations, including the process of evolution.

WAIT! There is more to read… read on »

What Does a Chemist Do with Excess Sodium?

Posted by jlwile on August 8, 2009

Alkali metals (like sodium) really like to give up their last electron. That way, they have a very stable electron configuration. Well…one way these metals can give up their electron is to react with water:

2Na + 2H2O –> 2NaOH + H2

In NaOH, the sodium is in its ionic form, Na+. Thus, it has lost its last electron and is now quite stable. Note that hydrogen gas is a product. Well, hydrogen is an explosive gas, and this reaction produces a lot of heat. So when sodium and water react…


Click here to see what happens

Note that this was done in a drainage pond with the owner’s full permission. There were no fish in the water, and the byproduct, NaOH, is actually good for the soil in this area, as the soil is acidic. Thus, this is an environmentally friendly shenanigan.

It turns out that of all alkali metals, sodium is the SECOND LEAST reactive. Lithium is the least reactive. The other alkali metals, in order of reactivity, are potassium, rubidium, cesium, and francium.

Anyone know where I can get some francium?