Matter and Measurements

Yesterday we started a new unit, on matter and measurement. For the most part I feel as if I knew a big chunk of this information before starting this, because most of the material so far seems familiar. Some new thing are the heating and cooling curve, more distinct classification of matter (heterogeneous mixture, homogeneous mixture, etc.), and significant figures.

Heating Cooling Curve

Significant figures seem confusing to me, and some of the law seem a little pointless. Found a webpage that puts all of the rules and examples in a simple way. 

We got a new project that seems relevant to what we are learning, taking measurements of ingredients of meals and putting them into metric. I like how I can easily see the relationship between the project and the unit it was tied to, which I had trouble with in earlier projects.

Aspirin Lab

Sadly this is not a lab that I will be participating in. Basically it was a high level lab that involves creating aspirin (acetylsalicylic acid), and I understand next to nothing on how this happens. The initial setup looks like this:

This would take chemicals acetic anhydride and salicylic acid and combine them together using the catalyst sulfuric acid. Chemicals are heated up in a hot water bath and then cooled with ice water to induce crystallization. The chemicals are left overnight. The next day the solid aspirin is added to the top of this:

In this section, the crystals are cleaned up of residual. This is were my class would stop, but in the full lab, the aspirin is purified  by dissolving the crystals and recrystallizing them.

This lab was higher than mine and my classmates understand at this time, but hopefully I'll understand as the year progresses.

Nuclear Fusion and Fission

Nuclear fusion sound amazing when you think about it. Taking two elements smashing them together to create a new, heavier element sounds like it comes out of a science fiction movie. The fact that it can be used to create energy without the harmful radioactivity, like it can in fission, can mean a lot of green opportunity, and we are closer to this than you might think.

It's also cool that the only place we know of nuclear fusion happening is in a top of a line lab, like this

and at the center of stars. Stars create elements, and that seem crazy to me.

Nuclear fission, on the other hand, is the spitting of an atom into two lighter ones. And we do this, like a lot. Around 25% of electricity in the U.S. is created with fission, and a lot more in France, around 85%! A fifth of the world energy is provided by nuclear power plants, even though they might have some fundamental problems.

Overall, fission and fusion seems pretty cool, even if it can be dangerous.

Forensic Archaeology

In this lab that we were given on Monday my lab partner and I were given a situation where we had to find the half life of imaginary atoms. This was done by using small squares that had a dark side and a white side. 567 squares were put into a cup and randomly poured on the table. The paper squares with the white sides were taken out. This was repeated six times.

When doing this experiment, I started to wonder how often the half life of an object is correct. Is the half life more of average time, or an exact time. By what Mrs. Frankenburg has said, it seems that the half life is always correct. In statistics I've learned about predicted lines, and I think that the lines of a half life graph are probably the predicted lines, but probably a good average due to extensive research on atoms. 

Forensic archaeology is the application of archaeology to criminal investigations. Part of archaeology is using the half life to predict the age of something, such as a old human items. The main use of forensic archaeology is to figure out the age of a body, similar to the what we were doing in the lab.

Weekly Quiz

Today was the weekly quiz over everything that we have learned so far. I feel like I did pretty well except for the last 8 or so questions, which where about what scientist had a certain model for the atom or the way they figured out their model for the atom. There was a lot on Isotopic Symbols which were pretty simple but I couldn't for the life of me remember the difference in between JJ Thompson, the Bohr Model, and Retherford's gold foil experiment.

Issues with Isotopes

Elements come in one variety, that would be too simple. Isotopes are atoms of the same element with different masses. This is possible because atoms of the same element can have different number of neutrons, subatomic particles with no charge that give the atom mass.

Wow

So basically most elements on the periodic table have two or more forms of themselves, which can have different properties. Although I've known of isotopes for a long time, mainly because of Hank Green and SciShow, I've never really thought about how they worked or or written out, in an isotopic symbol, which looks like:

While I don't think it's all that confusing, chemistry, elements, and just life in general, just got a little harder. 

Astrochemisty

For the next project in class, we are learning about astrochemistry. Astrochemistry can be defined "study of the abundance and reactions of chemical elements and molecules in the universe, and their interaction with radiation", which ties in well to our unit on atomic structure and radioactivity. As you would probally guess, NASA would be a major part of research in the US. 

This project is mainly about identifying solar bodies and their chemical make-up, and doesn't seem that hard, and rather more interesting than the last project.