Sunday, October 23, 2011

In the lab today we disected a chicken wing. We saw how a uses its muscles to move. when the wing wants to move it flexes it biceps to move it arm. Then it uses triceps to move into normal position. This is how it moves its arm.

Sunday, October 16, 2011

The main purpose in the diffusion lab was to separate. In the lab we used an indicator to see the different levels of concentration. The lab iodine solution in the baggie made the molecules in the baggie very hypertonic. The baggie was dilute and let the iodine solution to pass right through small holes. The different concentrations in substances, starch and iodine caused osmosis. The starch was hypotonic which caused the hypertonic iodine to fuse and change color. When the iodine moved both solutions became isotonic. My original prediction was that was that the iodine would change color because I knew that an indicator (the iodine) would indicate by changing color. My original prediction was that overtime the starch would change color. My prediction of the starch changing color was accurate.

In the lab many people noticed that water was a very crucial ingredient for the lab. It was the very first ingredient that we were supposed to put into a beaker. We needed an awful lot of water to finish. After the iodine was placed in the water, the color was splitting outward to cover all the water. This step is also called diffusion. A small plastic baggie was given to us and we were told to put some starch. Then, we had to place 250 Mls of water inside the plastic baggie. I noticed that the starch had turned to a thick yogurt-like substance. After many minutes there was a slight change in the colors. The water was getting lighter in color and the starch was turning to a color somewhere between purple and light black.

There have been many times when I’ve seen diffusion in the world. For example, when someone eats a bowl of cereal I see that after a few minutes the white milk starts changing until it looks like it is a very light brown. The milk changed color because the cereal (Honey Nut Cheerios) is brown. Another example of a time I’ve seen diffusion is when someone sprays perfume into the air. The molecules spread out causing the air to smell like perfume. Also, I have seen diffusion when something is being cooked or boiled, the steam rises into the air and moves outward since it can’t be all compressed into one small area. There are many other ways to see diffusion in any place. Another way to represent diffusion is by opening a door. When the door starts to open light leaks in through a small gap in the door. As the door opens more light spreads out throughout the air causing diffusion. There are many ways to show diffusion and this is only a few examples. There are many more examples of diffusion.