On 12 March 2016, a video purportedly showing Walmart-brand drinking water turning into an indigestible gelatin-like substance after being poured out into a bowl went viral on Facebook:
Bought this water at Walmart yesterday while in Washington...opened it to give water to dogs and it turned in a gelatin substance...WTH is this?????
Posted by Cathy Thomas on Saturday, March 12, 2016
The above-displayed video is real, but it doesn't capture water transforming into a strange "gelatin substance" — this video simply shows water turning to ice.
While water can freeze at temperatures as warm as 32°F, purified water can remain in a liquid state at temperatures below -40°F This "supercooled" water will instantly turn to ice when it is disturbed, due to a process known as nucleation:
Nucleation is a physical process in which a change of state — for example, liquid to solid — occurs in a substance around certain focal points, known as nuclei. Common examples are the condensation of water vapor into droplets in the atmosphere, the formation of ice crystals when water freezes, and the appearance of gas bubbles in a liquid. Heterogeneous nucleation happens in cases where there are pre-existing nuclei present, such as tiny dust particles suspended in a liquid or gas. Homogenous nucleation occurs where no such contaminants are present, and is much less commonly seen. This physical reaction is the basis for a variety of manufacturing processes and interesting natural phenomena.
In July 2014, Live Science demonstrated how supercooled water instantly turns to ice when poured out of the bottle, replicating an experiment that can be done by just about anyone with a freezer, some purified water, and a couple of hours:
Everyone knows that water freezes at 0°C — or does it? When water freezes, it needs a nucleus in order for the solid crystals to form and become ice. Water is typically full of particles and impurities which have no problem kicking off the crystallization process. However, purified water by definition doesn’t have those impurities. With nothing for the water molecules to latch onto, purified water can be supercooled as far as -40°C.
The energy generated from firm hit on the side of the bottle forces the supercooled water molecules to form a crystal in a process called nucleation. That nucleus ice crystal is all that’s needed to start a chain reaction of crystallization throughout the entire bottle. Shaking or jostling the bottle has the same effect, so be very careful and have a steady hand when removing the water from your freezer.
This viral Facebook video does not demonstrate any flaws related to Walmart-brand water, nor water transforming into a strange "gelatin substance." This video shows supercooled water turning to ice, a phenomenon that can be replicated with any brand of purified water.