sweet salt water science experiment

I am so excited about this experiment! Basically the students are going to observe and measure the characteristics of water as a liquid and a solid but with a twist. They are going to note the differences between fresh water and salt water. First, they need to think of questions by going to Google Earth and the internet they will look at pictures of the ice bergs, describe the temperature and then hypothesize why there are ice bergs in the Arctic Ocean but not in the Great Salt Lake. After, they will complete the experiment of freezing fresh water and ice water and then recording the differences every 20 minutes. After we will discuss the application of this knowledge as we make ice cream in a bag using salt and ice cubes to make it freeze!

Content:

Grade 1, Objective 2 Investigate water and interactions with water. a. Observe and measure characteristics of water as a solid and a liquid.

Pedagogy:

Observe the difference in salt water freezing vs. regular water

Plan an investigation of the differences by recording the temperature of water when in a liquid state moving to a freezing state through the digital probe

How does knowing this help us? (ice cream in a baggie, put salt on steps when it’s icy outside)

ICE CREAM IN A BAGGIE:

Put in a sandwich-size Zip-Loc bag and 'zip' closed:
- 1 tablespoon sugar
-1/2 cup milk
- 1/4 teaspoon vanilla

Put in a gallon-size Zip-Loc bag and 'zip' closed:
- the filled and zipped sandwich bag from above
- 2 tablespoons rock salt
- enough ice cubes to almost fill the bag

Shake and roll the big bag over and over, until the inner mixture is frozen (about 20 min.)

Technology:

Google Earth: Observe the different bodies of water at different times in the year

Ask questions: Why doesn’t the Great Salt Lake freeze? Where are the ice bergs in the Great Salt Lake when it is below freezing outside?

Why does the Arctic ocean have icebergs?

Temperature Probe: Have the students record data of freezing temperatures every 20 minutes on a chart from room temperature until the liquids are both frozen. Look at the data and make observations

Use the internet to look at different resources that show the temperature of the Great Salt Lake vs. The North Pole

Great Salt Lake

http://www.met.utah.edu/research/saltlake/Monitor

Arctic Ocean

http://www.thepoles.com/expguide/weathernp.htm