Reflection Journal #1

During the past 2 weeks of class, we did several experiments to get an idea of what we are in store for this year in chemistry. 

One experiment we did that I liked a lot were when we tested the physical and chemical change in matter.  I liked this experiment because it was very hands-on, which I always like in an experiment.  The main ideas in these experiments were to realize that not everything is a physical change, based on what we can plainly see.  Another activity we did in class, that had the same idea as the previous activity, was when we recorded positive/negative/zero change and physical or chemical changes with the steel wool, precipitates, ice and water, alka seltzer, and the dissolving sugar.  We concluded that, most of the time, there was no change among the testers.  However, although there was no change, mass wise, there were a lot of changes between the physical and chemical aspects.  For example, with the steel wool, when we weighed it in the beginning, its volume was smaller than it was after we pulled it apart; the mass didn't change throughout the experiment.  So, even though its volume changed, its mass wasn't, and it was a physical change.  Another experiment we ran in this activity was when we combined two liquids to form a new substance.  In the beginning, one of the liquids was clear, and the other was pink.  Initially, I thought that after we would combine the two, the new substance would be an even lighter pink.  However, after we actually mixed them, it turned thick and turned a dark, blood-red color.  This contradicted my thoughts and made me think twice about what could happen in the future.   With this experiment too, when we measured the two separate liquids in the beginning, the mass didn't change after we combined them.  Instead, the volume increased.  This experiment was a chemical change as well, although the color of the new substance was different.  It was a chemical change because it made a new substance. 

In conclusion, after we ran all these experiments, I understood that there can be a physical or chemical change even though there isn't necessarily a change in mass or volume.  Throughout the past few weeks, I didn't really have any particular questions; I understood fairly well what I was doing in every task.  I think my participation in the learning process was good.  I participated often in class, as well as when we were in groups running the experiments.  I think I need to work more on going the extra mile, as far as getting the answers I need to the questions I do ask myself (when I think of questions).  

Video of my favorite part of the experiment we ran (burning the magnesium ribbon)