Supercooling water and snap freezing

[ajp1972]

Hi, my son need help with procedure for this project. How would he take reading? Also, he needs help with chart and graph.
Thanks
Ashish

[JasonS]

Hello Ashish,

You'll need a thermometer to take the readings. Science Buddies recommends:

thermometer (good range would be -10°C to 110°C, e.g. part number 3113300 from Edmund Scientific's at scientificsonline.com)

As you go threw the steps of the experiment you would take a reading every minute let's say and then record that reading in your lab book.

For further info see the following links:

Bibliography

This project is based on:
Heya, R.N. & Mori, Y., 1999. "Supercooling," [accessed March 20, 2007] http://homepage3.nifty.com/Kume/naru/044/naru044e.html.

Gregorius, R., Hoff, and V. Calder, 2004. "Supercooled Water Demonstration," Ask A Scientist, General Science Archive, Argonne National Laboratory, U.S. Department of Energy http://www.newton.dep.anl.gov/askasci/g ... n01672.htm.

Gourmetsleuth, 2006. "Gram Conversion Calculator," GourmetSleuth.com [accessed March 20, 2007] http://www.gourmetsleuth.com/gram_calc.htm.

This animation illustrates the phases of water, from solid to liquid to vapor, as heat is added. Notice when the thermometer rises, and when it stays still:
Schurko, R., 2006. "Phases of Water," Department of Chemistry and Biochemistry, University of Windsor, Ontario [accessed March 20, 2007] http://mutuslab.cs.uwindsor.ca/schurko/ ... _water.htm.

[ajp1972]

Hi Jason,
Thanks for reply. That helped him to get started with the experiment. He got the thermometer that was recommended, and also steps were followed. He did the experiment with three different types of water ( tap, distilled, and dasani ) . Also he took reading every 2 minutes for 20 minutes. My question to you is that he should wait until it goes down to -1 to -3 Celsius or stop at 20 minutes ( his lowest temp was 4 degree Celsius ). Because he wants to do it snap freezes? Does he needs to boil the water and cool down before the experiment or wait more than 20 minutes until it goes down to -1 Celsius? Does it help to use glass cup to help temp to gown faster till -1 Celsius ? He needs to do two more experiments. So if you can give answers to this.
Thanks again

[wendellwiggins]

Hello ajp1972,

The exact length of time it takes your water to cool depends on several factors such as how much salt you put in the ice, how thick is your glass cup, and many others. The cup and water must remain in the ice/salt until it goes below 0 degrees Celsius or it will never freeze.

The temperature of the water when you put it in the ice/salt is not very important. Of course, if it is hot, it will melt more of the ice before it reaches 0 degrees.

Good luck, WW

[ajp1972]

Hi,
Thank you for your response. I need help with the graph. I will give my information and see what we can come up with. We have taken temperature every 2 minutes till 25 minutes until it freezes. Temperature starts from 22 degree Celsius to -3 degree Celsius. And we have different types of water ( distilled, tap, and dasani ) tested three times. We need to have time, temperature, and different types of water on the graph. So, if you can help how we could do this?
Thank you

[John Dreher]

Here is a link to a page that will make a simple graph of three quantities versus time. You would use it to plot the average of each set of data points. By hand you would then add little bars showing the range of the data represented by the averaged data (highest to lowest vertical line through each symbol for example). Good luck.

http://nces.ed.gov/nceskids/graphing/cl ... tallines=3

There are many other web gadgets that do similar tasks. They are easy to find using google searches like
"how to make a graph -excel" (the "-exel" removes links explaining how to use the program called Excel to
to this task -- if you have Excel on your computer you could also use it to make a graph, but it's trickier to use
than the web gadget at the above URL).