Blog #4

This unit on chemical equations has been my favorite so far this year. The beginning of the unit, with nothing but balancing chemical equations, was incredibly easy. It's so weird to be able to grasp something so quickly in this class, which is a tad depressing to say. After everyone had at least a basic grasp on balancing equations, we moved on to predicting the outcome of chemical reactions and identifying the type of reaction. For this, we did an experiment where we mixed chemicals and had to identify the product. It was definitely more fun than some of the experiments we've done this year, and it was really cool to see how different chemicals combined.  This wasn't very difficult, although the homework assignment on this did require a bit of flipping around in my notebook to make sure I'm identifying the equation correctly. In addition to this, I still needed to doublecheck the charges on a lot of elements and compounds. I'm learning them, though. The final thing we tacked on to this unit was the LOLOL energy charts. I'm still not too confident with this, and am having flashbacks to earlier in the school year. However, I should be able to do it with a little more practice. I can identify how the energy flow works, and I count that as a tiny success. I can't remember where it fit into my chronological list of this unit, but we also talked about the reactivity of different metals. It makes a lot of sense for some metals to be more reactive than others, since I don't think a lot would happen if they were all equally reactive. In conclusion, I like this unit a lot, and will be kind of sad when it's over.

An example of a balanced chemical equation. This is a combustion reaction, since the hydrocarbon reacts with oxygen to produce carbon dioxide and water.

I found this on Google Images as an example of a single replacement reaction and it made me laugh.

Blog #3

We started this unit learning about relative mass, and how the atomic masses on the periodic table are based on the atomic weight of carbon - 12 grams. I thought this made sense, as it then led directly into the work on Avogadro's Number, or 6.02 x 10^23 atoms. This is also known as a mole. I had more trouble than I would like to admit with the proportions, and once it finally started to click we were moving on. Luckily, this was something repeated throughout the rest of the unit, so I think I'm starting to get a pretty good grasp on it. Going back to the atomic weight of carbon, molar mass is exactly that. The atomic weight. It's the mass of a single mole of anything shown in grams. The proportions I was talking about my difficulties with involve changing moles to grams, number of atoms to grams, and number of atoms to moles, and vice versa for all of those. I do think I'm starting to get the hang of it, although I can't say I'll be particularly upset when we move on from this unit. I honestly don't remember doing a lot of lab work this unit, though. The only one I remember is the one from a few days ago, where we put the zinc in the hydrochloric acid and made zinc chloride. This was part of our most recent topic, percentage composition. Percentage composition is how much of a compound is made up of different atoms, such as water being made up of two hydrogen atoms and one oxygen atom. I actually don't mind this part of it as much. Solving to find the empirical formulas is kind of like solving a puzzle, and actually a bit fun. Hopefully everything starts to come together soon.

A picture of zinc chloride. I, unfortunately, did not take this, but thanks to Wikipedia I was able to find a similar picture. The stuff Kate and I made was actually more of a brownish color, which could be because I spilled some of the acid all over the lab table. Oops.

This picture I did take. It's a very flattering shot of everyone's best friend, the mole puppet. Which is actually a rat, but we don't talk about that.