Buzz
Water is typically known to exist as a solid, liquid, or gas, right? Not quite! It can take on several other states and forms, some of which you might find unbelievable. For example, did you know water can turn into hot ice or even powder? Yes, powdered water actually exists.
You might be wondering, “How can that even be possible?” Well, the answer depends on various factors, with temperature and pressure being two of the most important. In other situations, strange phenomena occur when water interacts with other substances.
10. Ice-VII
Ice is cold, but not ice-VII (also known as hot ice), which is actually quite hot. The regular ice we encounter on Earth is referred to as “ice Ih.” The “h” denotes hexagonal, as the oxygen atoms form a hexagon shape when water freezes under standard pressure.
However, ice Ih transforms into ice-II when exposed to more pressure. As pressure continues to increase, it turns into ice-III, and the cycle continues until it reaches (or even exceeds) ice-VII, where the oxygen atoms form a cubic arrangement.
Ice-VII is hot because it only forms under extreme temperature and pressure conditions. On Earth, it could theoretically only exist deep within the mantle, where the pressure is strong enough to force regular water into ice-VII. However, it won't actually form there because the intense heat would vaporize the water before the pressure could convert it into ice.
Scientists have managed to recreate ice-VII in the lab. They’ve also discovered it within diamonds that formed deep inside the Earth’s mantle. The ice formed when water droplets were trapped in the diamonds as they were created under extreme pressure.
9. Dry Water
Dry water is created by mixing natural water with silica, aided by a machine. It has the appearance and properties of a solid, even though it's made up of 95% water. The mixture consists of powdery grains, similar to sugar, which are actually water droplets coated in silica. This silica layer prevents the water from becoming liquid.
First developed in 1968, dry water was initially used in cosmetics. It was largely forgotten until it was rediscovered by researchers from the University of Hull, UK, in 2006.
Scientists believe dry water might be used to absorb carbon dioxide from the atmosphere, as it can absorb three times more carbon dioxide than regular water. It is also being explored as a potential method for safely storing and transporting hazardous chemicals.
8. Supercritical Water
A substance reaches a supercritical state when both its temperature and pressure are so high that the distinction between its liquid and gaseous forms disappears. For water, this occurs after the gas phase. So water progresses in this order: solid, liquid, gas, and then supercritical. At this stage, water exists as a strange vapor that isn’t quite a gas.
Water enters its supercritical state at a temperature of 373 degrees Celsius (703 °F) and a pressure of 220 bars. At this point, it cannot be reverted back into a liquid. Supercritical water, like other supercritical fluids, can flow through solids like a gas but retains the ability to dissolve other substances like a liquid.
7. Plasma Water
Gliese 1214 b is a truly bizarre planet. It's six times the size of Earth and entirely filled with water—including water in a plasma state.
Matter in a plasma state resembles a gas in some ways. It has a low density and lacks a fixed shape or volume, just like gas. However, unlike gas, the atoms in plasma have had their electrons stripped away, leaving behind positively charged nuclei that move freely. This is why many scientists consider plasma to be the electrically charged version of gas.
Back to Gliese 1214 b. This planet orbits so close to its star that a year there lasts just 38 hours. In comparison, Earth is 70 times farther from the Sun. The temperature during the day on Gliese 1214 b could reach up to 282 degrees Celsius (540 °F), making it far too hot for most forms of life to survive.
Gliese 1214 b’s proximity to its star explains why water might exist as plasma there. The extreme heat from the star, combined with the planet’s high pressure, causes water to become so hot and compressed that it turns into plasma. Plasma water is considered one of the supercritical forms of water we’ve discussed earlier.
6. Triple Point Of Water
The triple point of a substance occurs when its solid, liquid, and gaseous states all exist simultaneously in thermodynamic equilibrium. This can only happen at a specific temperature and pressure. For water, these conditions are 273.16 degrees Kelvin (0.01 °C, 32.02 °F) and 611.66 pascals (6.1166 mbar, 0.0060366 atm).
The triple point of water is a key reference for determining temperature in Kelvin, calibrating thermometers, and defining the triple points of other substances. At its triple point, water can easily transition between solid, liquid, and gas states just by adjusting its pressure and temperature accordingly.
5. Superionic Ice
Superionic ice, also known as ice-XVIII, is a unique form of ice created by an extreme increase in both temperature and pressure. This version of ice is hot, dark, dense, and behaves similarly to metal. A solid cube of ice-XVIII weighs four times as much as a similar-sized cube of regular ice. Some scientists believe that ice-XVIII could be the most common form of water in the universe, existing on “ice giant” planets like Uranus and Neptune.
Interestingly, the existence of ice-XVIII was only confirmed in 2019, despite being predicted in 1988. That year, a group of researchers proposed that water would act like a metal under extreme temperature and pressure. Ice-XVIII forms only when temperatures reach thousands of degrees and pressures exceed millions of atmospheres.
In an experiment, scientists confirmed the existence of ice-XVIII by using powerful lasers to generate shock waves that rapidly increased the temperature and pressure of a droplet of water. As the water transformed into crystalline ice, the hydrogen and oxygen molecules were observed to instantly separate.
The oxygen molecules formed solid, frozen structures known as cubic lattices, while the hydrogen atoms flowed like a liquid around the hardened oxygen. Some scientists argue that this “ice” cannot be considered water because the hydrogen and oxygen molecules have separated. They contend that the two need to remain together for it to truly be water.
4. Aeroice
Aeroice is the lightest form of ice discovered so far. It was “discovered” in a 2017 simulation by researchers at Okayama University in Japan during an experiment to understand how water turns into ice. The team created this ice while investigating what happens when water freezes in the absence of pressure.
The other forms of ice we’ve mentioned were created after immense pressure was applied to water. This particular simulation focused on the effects of negative pressure.
To create aeroice, the scientists first extracted the two oxygen atoms from silicon dioxide (also known as silica), leaving only the silicon behind. They then replaced the silicon atom with an oxygen atom before adding two hydrogen atoms to form ice. This discovery may have implications for understanding how water behaves in environments like nanotubes, nanopores, and various other parts of the cosmos.
3. Quantum Water
In 2016, researchers at the United States Department of Energy’s Oak Ridge National Laboratory uncovered a new quantum state of water. They made this breakthrough by “squeezing” water molecules between hexagonal beryl crystals.
The intense compression created such high pressure that the water molecules’ atoms became misaligned, causing the water to no longer obey certain laws of physics. In this state, the molecules could pass through atomic barriers, a phenomenon explained by quantum mechanics, known as “tunneling.”
This phenomenon is unique to substances in a quantum state. Scientists hypothesize that water shifts into a quantum state to navigate through extremely confined spaces in rocks, soil, and even the membranes of living cells.
2. Combustible Ice
Methane hydrates are a form of ice that can actually burn, similar to setting paper on fire. This ice contains methane and naturally forms at specific ocean depths, in permafrost, and even within oil and gas pipelines, where it can create blockages. The discovery of this burning ice dates back to the 1930s.
Burning ice starts as compressed, frozen methane, which is then enveloped by ice, transforming into burning ice. Scientists view this ice as a potential fuel source due to its methane content. A cubic meter of burning ice can release 160 cubic meters of methane. It's also considered a cleaner alternative to coal.
Unfortunately, many nations are unable to substitute their coal usage with burning ice due to the difficulty of extracting it from underwater. Furthermore, it becomes unstable once it is brought to the surface. Some scientists warn that burning ice could inadvertently contribute to climate change by releasing methane into the atmosphere when methane hydrate-laden permafrost thaws.
1. Amorphous Ice
Amorphous ice forms when liquid water is rapidly cooled, preventing the molecules from organizing into a crystal lattice. Without the usual ordered crystalline structure found in regular ice, amorphous ice is typically regarded as a form of glass—a state of liquid that moves at an extremely slow pace. Although uncommon on Earth, it is believed to be the most widespread type of water in the universe.
A 2017 study involving computer simulations of amorphous ice suggested that glasses may represent an intermediate state between crystalline and liquid forms. The simulated amorphous ice exhibited disordered hyperuniformity, where there is long-range order but no short-range order.
