It’s not fully clear which specific clip or story you’re referring to with “what are they trying to freeze in the water,” but there are a few common contexts where people deliberately try to freeze something in water in a way that often shows up in news, forums, or science videos.

Below are the most likely possibilities and how they work.

1. Supercooled water experiments

In many science videos and posts, people cool pure water below its normal freezing point (0°C) without it turning into ice right away.

  • They are effectively trying to “freeze” pure liquid water itself in a dramatic way.
  • When they tap the bottle or pour it onto ice, it suddenly crystallizes into ice almost instantly, which looks like “freezing on command.”
  • This works best with very clean water and a very still container, because ice crystals need a starting point (a “nucleation site”) to grow.

So in that context, the answer is: they’re trying to freeze supercooled liquid water itself in a controlled, visually dramatic way.

2. Freezing water under pressure (what if you “don’t let it expand”?)

Some physics videos explore what happens if you cool water in a rigid container so it can’t expand easily as it freezes.

  • Normally, when water freezes, it expands; that’s why ice floats and why containers can crack in the freezer.
  • If you prevent expansion, the forming ice creates pressure on the remaining liquid, and high pressure actually tends to melt ice.
  • At even higher pressures and low temperatures, water can freeze into other, denser forms of ice (such as “ice III”), which don’t expand the same way.

In that scenario, they’re trying to freeze water into different high‑pressure ice phases inside the water, while it’s constrained.

3. Freezing what’s in the water (solutes or structures)

In some experiments and practical setups, the goal isn’t just to freeze water, but to freeze what is suspended or dissolved in it. Common examples:

  • Salt and impurities : As lakes freeze, the first “black ice” is very clear and strong, and impurities are pushed aside, changing the water underneath.
  • Foods like ice cream/popsicles : Technologists sometimes use special proteins (like those found in Antarctic fish) to control how ice crystals form in water‑based mixtures so they don’t get large and gritty.
  • Biological material : In lab contexts, people freeze water around cells, proteins, or small structures to preserve or image them, trying to control crystal formation so it doesn’t damage the sample.

Here, you could say: they’re trying to freeze the water in a way that protects or structures whatever is inside it (salt, sugar mixtures, biological samples, etc.).

4. Everyday “freezing in water” you might see online

You’ll also see more casual or viral versions of this idea:

  • Guides and infographics about how not to get trapped in icy water , which talk about how quickly water freezes and how ice forms on surfaces.
  • Classroom demos where a metal can is cooled with ice and salt so that water from the air first condenses, then freezes on the outside , showing liquid water turning to ice on contact.

In these, what’s being frozen is often either the water in the air (condensing on a cold surface) or surface water in a dangerous environment (like an icy lake).

If you meant a specific clip or meme

The phrase “what are they trying to freeze in the water” sounds like something someone might say in a comment under:

  • A science/physics video showing weird freezing behavior.
  • A TikTok or forum clip where people are doing some risky stunt on thin ice or a frozen pool.

If you can describe:

  • Where you saw it (YouTube, TikTok, Reddit, news), and
  • What was happening visually (bottle, pipe, lake, lab setup, etc.),

I can narrow it down and tell you much more precisely what they’re actually trying to freeze and why it behaves that way.