We recently came across this video by SooToday.com‘s reader Phil Sabine making its rounds on the Internet. In the video, Sabine takes a cold bottle of water, turns it upside down and then taps the bottom. The water instantly begins freezing from the bottom down to the top.
Is it magic? A slight of hand? Or did he switch the liquid in the bottle to something other than water?
The answer to all of the questions is no, there is no trick. The solution lies in the science behind the freezing temperature of water and how ice crystals form. This is also referred to as Supercooled Water.
Everyone knows the freezing temperature of water is 32 degrees Fahrenheit or 0 degrees Celsius. When this temperature is reached, the water molecules freeze by forming ice crystals. It’s easier for the water molecules to turn to ice on top of already formed crystals. Ice crystals build on existing ice crystals to eventually freeze the entire bottle of water.
What starts the freezing ice crystal process?
The process of starting the ice crystals is called “nucleation.” This starts from an impurity or scratch or piece of dust on the container holding the water. In this case, the water bottle. One ice crystal attaches to the imperfection, and the others grow on top.
What if the water bottle does not have an imperfection or impurity? Nucleation cannot begin, and the water stays in its liquid state. Even in temperatures below the freezing point. This state is called “metastable.” The water stays liquid until something kicks off the nucleation process.
In the SooCool video, Phil turns the bottle upside down and smacks it. This is enough to start the ice crystals to form and build on top of each other as they freeze down the bottle.
The water in the bottle isn’t frozen solid, but more slushy.
For an experiment, take a case of water and place it in the freezer. Keep all of the bottles in the same position and try not to make any dents or flaws in the plastic. Wait overnight and check the water. Some of the bottles may still be liquid. If this is the case, try different techniques of shaking, hitting or disturbing the water in the bottle to see if the water will instantly freeze.
Instant Freeze Soda
Did you know soda will also instantly freeze? Here’s a video of Steve demonstrating this on 9News. You can also read step by step directions and the science behind the Instant Freeze Soda on the experiment page.