· Step 1: Put ice in the Ice Cream Ball on one side, and add ½ cup of ice. Close the side.
· Step 2: Mix these ingredients in a bowl: 1 Tablespoon sugar, 1/2 cup cream and ½ teaspoon vanilla.
· Step 3: Open the other side of the Ice Cream Ball and pour in the mixed ingredients. Close the side.
· Step 4: Have a “ball”! Roll the ball to your friends for 10 to 15 minutes (but no kicking or throwing, or it can break).
· Step 5: Open the ice cream side and use a spatula to empty out the ice cream. Serve and enjoy!
How does it work?
First watch the video to see what we did. The secret was to lower the freezing point of the ice! How did we do this? With salt! When salt is mixed with ice, it lowers the freezing point of the ice and causes it to melt. The more salt added, the lower the temperature will be before the salt-water solution freezes. Another way to say this is that the heat (energy) of the cream was sucked up (absorbed) with the help of the salt, and it’s called “endothermic”.
P.S. (An explanation for older kids) A 10% salt solution freezes at 20 degrees Fahrenheit instead of 32 degrees Fahrenheit.