• Ice CreamIce Cream in a Baggy
     
    The Scientific Method
     

    Question:

    Will salt change the freezing temperature?

     

    What is your hypothesis?

     

     Materials

    ·                            1/2 cup milk

    ·                            1/2 cup whipping cream (heavy cream)

    ·                            1/4 cup sugar

    ·                            1/4 teaspoon vanilla

    ·                            1/2 to 3/4 cup sodium chloride (NaCl) salt

    ·                            2 cups ice

    ·                            1-quart baggy

    ·                            1-gallon baggy

    ·                            thermometer

    ·                            measuring cups and spoons

    ·                            cups and spoons for eating your treat!

     

    Procedure:

     

    In the Small Baggiy:

    1.                  Add 1/4 cup sugar

    2.                  1/2 cup milk

    3.                  1/2 cup whipping cream

    4.                  1/4 teaspoon vanilla

    Seal the bag SECURELY!

    In the Large Baggiy:

    1.         Put 2 cups of ice – Measure the temperature of the ice in the gallon bag.

    2.         Add 1/2 to 3/4 cup salt (sodium chloride)

     

    Ø     Place the sealed quart bag inside the gallon bag of ice and salt. Add more ice to fill the gallon bag.  Seal the gallon bag SECURELY.

    Ø     Gently rock the gallon bag from side to side holding it by the top seal. Or roll it between towels since the bag will be cold enough to damage your skin.

    Ø     Continue to rock the bag for 10-15 minutes or until the contents of the quart bag have solidified into ice cream.

    Ø     Open the large bag and use the thermometer to measure and record the temperature of the ice/salt mixture.

    Ø     Remove the quart bag, open the ice cream and ENJOY!
     

    Results: 

    What was the temperature of the ice before adding salt?

    What was the temperature after adding salt? 
     
    Conclusion:
    Based on your temperature readings, if the ice had melted what does salt due to the freezing point?  
    it lowers the freezing point.  That is why the salt/ice/water solution's temperature is lower and still not completely frozen.  The new freezing point is -22 degrees C.   ; 0 )
     
    The Science Behind it....http://www.ehow.com/about_6512742_adding-water-lower-freezing-point_.html
     
    http://www.worsleyschool.net/science/files/saltandfreezing/ofwater.html
Last Modified on May 26, 2011