Domain: Natural Science — Physics
Target concept: When water changes from the liquid to the solid state (freezing), its volume expands.

Video generation prompt: Place a transparent container filled with liquid water into a household freezer or a salt-ice bath (ice mixed with salt to reach sub-zero temperatures). Allow the liquid water to cool and solidify. Then remove the container and observe its internal state.

Evaluation guide:
(i) Target concept: Water's anomalous expansion upon freezing.
Minimum mechanism: Liquid water must be initially present in a rigid, transparent, sealed or open-top container; thermal energy must be removed to induce phase transition; resulting solid ice must occupy greater volume than the original liquid, mechanically stressing the container.
(ii)Storyline: [Phase 1: Initial State] Transparent container centered in frame, filled with still, clear, flat-surfaced liquid water; no bubbles, particles, or surface disturbance. [Phase 2: Placement] Container is moved into a visible cold environment (freezer compartment interior with shelf/light, or a salt-ice bath with submerged container base, salt visibly mixed into the ice). [Phase 3: Transition] Gradual loss of clarity (clouding/frosting), followed by nucleation points, then full solidification; all within same spatial context. [Phase 4: Observation] Same container, now removed, shown frontally: expanded ice visibly deforming container geometry and elevating surface above original level. Perspective remains fixed; container never leaves frame or rotates; lighting remains consistent with ambient cold setting.

Manual:
Experimental Procedure
1. Fill a transparent container with clear liquid water until ~¾ full.
2. Place container into a household freezer compartment or a salt-ice bath (ice mixed with salt to reach sub-zero temperatures).
3. Wait until water completely solidifies.
4. Remove container and observe internal state.
Observation of Experimental Phenomena
Water expands upon freezing: solid ice occupies more volume than original liquid — visible as bulging container walls, raised convex surface above original fill line, or lid displacement.
Summary of Experimental Principles
When water changes from liquid to solid state (freezing), its volume expands — a rare property among substances due to hydrogen-bonded hexagonal crystal lattice formation.

Prompt Grounding rubric:
level_1: No transparent container appears in the video; no liquid water is shown at the start; the cold-environment placement step is absent; and no post-cooling removal/observation shot is shown.
level_2: A transparent container appears but its contents are not identifiable as clear liquid water at the outset (e.g., the container starts empty, colored, or already frozen); the move into a freezer compartment or salt-ice bath is skipped or only implied by a jump straight to a frozen block; there is no shot pairing the liquid state with the later solid state.
level_3: The transparent container is shown at the start holding a clear, still, featureless body of liquid water with a flat surface; the container is then shown placed into a visibly cold environment (either a freezer compartment or a bath of ice mixed with salt); the water is then shown progressing toward the frozen state, with at least some visible sign of change (such as clouding, frosting, or ice crystals forming) rather than a hard cut straight from clear liquid to a finished solid block; the same container reappears with its contents fully changed, matching the prompt's sequence of placement, cooling/solidification, removal, and observation.
level_4: Everything required for score 3 is present, and the cold environment is unambiguous: either a domestic freezer compartment (visible shelf, interior light, or frost-lined walls) or a salt-ice bath (ice chunks visibly mixed with granular salt surrounding the submerged container, not just plain ice cubes in water); the same container stays in the same framing across the placement and observation shots; no other container or object is substituted in between.
level_5: Everything required for score 4 is present, and the transparent container is the only focal object in every shot; its walls stay clear enough throughout that the ice/water inside remains visible (no persistent fogging or glare blocking the view); the liquid-to-solid change is shown as a continuous take or an accelerated/time-lapse sequence that keeps identical camera position, angle, and zoom on the container and includes visible intermediate clouding/crystallization before the final solid state: no repositioning, reframing, or hard cut that jumps directly from clear liquid to the finished solid block with no transition footage.

Scientific and Causal Correctness rubric:
level_1: The water inside the container stays liquid for the entire video, or turns to vapor/mist instead of ice, or freezes solid without any rise in level (e.g., the top surface stays flat or drops), or the frozen block visibly shrinks/cracks apart instead of bulging outward.
level_2: The water freezes solid, but the ice's top surface stays flat or lower than the original water line (no expansion shown); or the surface rises but the container shows no bulging, no dome-shaped top, and no lid/cap displacement; or the result looks like loose slush or wet granular ice rather than a single solid block.
level_3: The container's contents change from a fully liquid, flat, featureless body of water to a fully solid, rigid, non-flowing block of ice, AND the ice visibly takes up more space than the original water: the container's side walls bulge outward, or its lid/cap is pushed upward, or the ice surface rises above the original fill line into a convex, dome-like mound, matching the expected expansion of water on freezing.
level_4: Everything required for score 3 is present, AND the ice block itself looks like real ice rather than glass or resin: it is milky/cloudy rather than perfectly transparent, with a grainy or crystalline surface texture consistent with trapped air bubbles pushed out during freezing (visible air-bubble streaks or graininess are expected here, not disqualifying); there is no partial melting, dripping, or liquid pooling visible during the final observation.
level_5: Everything required for score 4 is present, AND the expansion is shown only as upward doming and/or outward bulging of the walls, never as sinking, sagging, or downward displacement of the ice; the finished ice block is confirmably larger in volume than the starting water, shown through at least two simultaneous visual cues in the same final shot: an outward-bulged side wall and a raised, convex ice surface sitting clearly above where the original water line was.

Spatiotemporal Consistency rubric:
level_1: The container vanishes and reappears at some point in the video, or the lighting jumps abruptly from one look to a completely different one with no matching change in environment, or the container's position/orientation suddenly jumps between shots, or the ice appears to snap from a flat surface straight to a bulging one with no visible in-between stage.
level_2: The container stays on screen the whole time but appears to drift, rotate, or slide with no visible support doing it; the cold-environment lighting (e.g., freezer interior light or the pale light around the salt-ice bath) brightens or dims for no environmental reason; the shadow cast by the container swings to a different direction without the light source moving; reflections on the container's surface suggest more than one inconsistent light source.
level_3: The container holds the same position, orientation, and size in every shot; the cool, even lighting of the freezer interior (or the ambient lighting around the salt-ice bath) stays the same in color and brightness across the placement and observation shots; the shadow the container casts keeps the same direction and softness throughout; the container's shape shows no stretching, warping, or other geometric distortion between frames.
level_4: Everything required for score 3 is present, AND the sequence of events runs in the correct order without skipping or reversing: clear liquid water is shown first, then a visible progression (surface clouding/frosting, then ice crystals forming, then the water fully solidifying, then the final bulged/domed shape) with no stage shown out of order (e.g., the bulge must not appear before any clouding or crystal formation is visible).
level_5: Everything required for score 4 is present, AND the motion between frames looks physically continuous, with no strobing, jitter, or repeated/frozen frames; the bulging or doming of the ice grows gradually across the transition rather than jumping straight to its final shape; any condensation that appears on the container's outer surface can appear as soon as that surface looks cold to the eye (a light frost or misting can start before the water has fully solidified inside, reflecting the fact that the outside cools faster than the inside finishes freezing).