Water, Ice, Water

Soooo, we did the the freezing and melting experiment on the 4th meeting of our Physics 103.1 lab class. It was quite a easy-to-do and fast experiment compared to our previous activities. On the other hand, I was extremely late that day... *sigh* I woke up 9AM whereas our lab class starts at the same time. Good thing I was still able to manage and take a bath and run all the way to NIP and end up 30 minutes late.

The Experiment

Going back to the experiment, we started with freezing water. We first took a test tube with around 5ml water and placed it on an ice bath using a iron stand just like the figure below:

this is the exact diagram of what we did in the lab!

Using awesome LabQuest, we measured the temperature of the water inside the test tube with the Thermo Sensor dipped on it. When the ice cubes on the beaker started melting, we added salt to further lower the temperature and continuously added more ice. We did this for 15 minutes. After that, we end up with a constant temperature of 0 degrees Celsius.

When set run 2 and this time, we removed the ice bath and let the ice formed inside the test tube melt. After 12 minutes, we submerged the test tube to a warm water bath. When the run automatically stopped, we were then set to analyze the data.

We then took the average of the flat parts of the two temperature vs. time graphs (which means they're constant). We came up with 0.12 degrees Celsius as the freezing point and 0 degrees Celsius as the melting point. Which is just close enough to the theoretical value.

Personal Insights
It was really, really simple. This experiment was quite straightforward, however, it was really hard to freeze the water... to actually make it solid ice. So we had to do it thrice (I think). Anyway it was literally cool to freeze water. Even though I came late, our group was still able to finish first, which is also a first. :))