To observe the physical changes of ice cream ingredients using NaCl to
lower the melting/freezing point of ice/water.
Large plastic bag
Milk Paper Bowls to eat out of
Half and half
1. Combine the following
materials in the plastic bag:
½ cup (120 ml) of milk.
½ cup (120 ml) of half and half.
1 cup (236 ml) of whipping cream.
½ cup (120 ml) sugar.
½ tablespoon (10 ml) vanilla.
bag and gently mix the contents in the bag.
Record observations of what the contents look like at 0.0 minutes.
Place a layer of crushed ice in the blue bin, so that it covers the
Sprinkle a layer of salt onto the ice.
Place your sealed bag of ice cream mix in the center of your bin (on the
Continue adding layers of ice and salt until it is near the top of the
Shake for 30 minutes.
After 30 minutes, check your bag; if it’s hard eat it. If it’s still
soft continue shaking.
Record observations. If
necessary, add more ice/salt to the bin.
for 20 more minutes.
Check your bag. Record
Open it up and…enjoy!
Observations: (15 points) At
0.0, 30.0 and 50.0 minutes write an
observation when the questions below apply.
Each observation should answer the following questions:
How molecules behave in a solid.
Is it a Mixture or a Solution?
Explain the physical changes that take place during this process.
The term thermodynamics = the transfer of heat.
Think about the thermodynamics of making ice cream… that is… think about the transfer of heat between substances: ice, salt, ice cream mix, environment.
a. Explain the thermodynamics of melting ice (while making ice cream).
b. Explain why the ice cream mix freezes… in terms of the transfer/flow of heat.
salt lowers the melting point of the ice.
why this is advantageous when making ice cream.
Is making ice cream a physical or chemical reaction?
Explain your choice.