August Activity
Month: August
Theme: Weather and Climate
Activity: Ice Experiments
Ice Experiments
Supplies:
- Small containers filled ¾ with water
- 6” pieces of string
- Ice cubes
- Salt
- Sugar, pepper
Directions:
Step 1: Put an ice cube in each container of water.
Step 2: Have kids place the string on the ice cube and tell them to try to pick up the ice cube. They won’t be able to.
Step 3: Now, tell them to lay the string along the top of the ice cube. Sprinkle sugar on the top of the string where it touches the ice cube. Does anything happen? (no).
Step 4: Repeat with pepper. Nothing will happen.
Step 5: Now try it with salt. Wait about 30 seconds and lift the string-the ice cube will be attached! It works best with ice cubes that have the largest surface area. Make sure to get the salt all along the string where it touches the ice.
How does it work? Well, basically salt lowers the freezing point of water. So water typically freezes at 32 degrees F (0 C), but when salt is added, the water has to reach an even colder temperature in order to freeze, which in effect causes melting. As the ice melts, enough heat leaves the ice cube to freeze the string onto the cube.
Ice cube racing
Try to race ice cube down different surfaces- see if there is a difference when the ice is very frozen, starting to melt or very melty. Does one slide down faster than another? What about on different fabrics?
