Things You'll Need
Instructions
Freezing Water
Place three plastic bottles of water in a bucket. Pour in a bag of ice. Add tap water until the ice in the bucket is slushy. Arrange the bottles so that their lids stay above the icy water. Pour in 750 grams of salt.
Move the bottles around in the salt water and place them so that they are evenly spaced. Place a thermostat in the bucket; let the bottles sit in the salt water for 30-45 minutes. Check on the bottles and move them around the salt water periodically during the 45-minute period.
Gently remove the bottles from the salt water when the thermometer reads -6 to -8 degrees C; the bottles are probably ready when a thin layer of ice appears around the bucket. Place a few ice cubes inside a glass bowl. Open one water bottle and pour it into the bowl. The liquid water will turn to ice as soon as it touches the ice cubes.
Freezing Liquids with Liquid Nitrogen
Obtain liquid nitrogen from a liquid gas supplier. Hospitals, laboratories, mortuaries and cryonics facilities buy liquid nitrogen in bulk. Ask at these sorts of facilities for a small amount of liquid nitrogen for your experiment. Provide the facility with your reasons for requesting liquid nitrogen along with a flask to deposit the liquid in.
Freeze liquids by putting them in contact with a cryogenic liquid such as liquid nitrogen. Cryogenic liquids will freeze other liquids immediately upon contact. Pour liquid nitrogen from a Dewar into a metal bowl. Pour the liquid nitrogen slowly to avoid splashing.
Pour water or another liquid from a bottle into the liquid nitrogen. The liquid will freeze instantly while you are pouring. Always use safety precautions, such as gloves and goggles, when handling cryogenic liquids as they can cause frostbite.