Domain: Natural Science — Chemistry
Target concept: Chemical garden experiment forming mineral chimney structures

Video generation prompt: A clear sodium silicate solution is placed in a glass container. Metal salt crystals are gently placed at the bottom of the container and no further stirring is performed.

Evaluation guide:
(i) Target concept: Osmotically driven precipitation growth at a solid-liquid interface forming vertically oriented, hollow, membrane-bound mineral chimneys.
Minimum mechanism: A soluble metal salt crystal must contact a supersaturated sodium silicate solution; local ion exchange must produce an insoluble silicate skin that acts as a semi-permeable membrane; water influx through the membrane must generate sufficient pressure to lift and extend the precipitate upward in a tubular fashion.
(ii)Storyline: [Frame 0–2] Static shot: clear liquid fills glass container, meniscus visible; crystals rest motionless on flat bottom surface. [Frame 3–5] First visible emergence: localized opacity or color change at crystal surface, followed by upward extension of a narrow, continuous column. [Frame 6–10] Sustained growth: column elongates vertically without bending, branching, or collapsing; base remains fixed; surrounding solution stays optically uniform; no secondary nucleation elsewhere. Perspective: fixed frontal view, centered on crystal(s) and lower third of container; full container height visible; no occlusion of crystal base or chimney base.

Manual:
Experimental Procedure
1. Pour clear sodium silicate solution into a transparent glass container until ~¾ full.
2. Gently place one or more dry metal salt crystals (e.g., cobalt chloride, copper sulfate) onto the bottom interior surface — no stirring or agitation.
Observation of Experimental Phenomena
Within seconds, vertical, hollow, tube-like mineral chimneys grow upward from the crystal surfaces; chimneys are opaque or colored, contrast sharply with the clear solution, and remain anchored at the crystal base.
Summary of Experimental Principles
Metal cations react with silicate anions to form insoluble metal silicates; osmotic pressure differences across semi-permeable precipitate membranes drive upward growth, forming chimney-like structures — a classic chemical garden phenomenon.

Prompt Grounding rubric:
level_1: No glass container visible; no sodium silicate solution present; no metal salt crystals shown; no placement action depicted; scene is unrelated to chemical garden setup.
level_2: Glass container is present and contains a liquid, but the liquid is not transparent/clear (e.g., cloudy, colored, or opaque); metal salt crystals are absent or incorrectly placed (e.g., floating, suspended, or on top of liquid); no placement action at bottom is shown.
level_3: Glass container is present with a clear, colorless liquid; metal salt crystals are present and located inside the container; placement action occurs (crystals are introduced into the container), but their final position is not verifiably at the bottom (e.g., partially submerged, drifting, or resting on side wall).
level_4: Glass container is present with a clear, colorless liquid; metal salt crystals are present, fully resting on the bottom interior surface of the container; no stirring or agitation is visible after placement; all objects match prompt-specified types and spatial arrangement.
level_5: Glass container is present with a clear, colorless liquid; metal salt crystals are present, fully resting on the bottom interior surface; placement action is clearly depicted as gentle deposition (no splashing, no hand/tool contact after release); no subsequent motion or disturbance occurs; container remains static and upright throughout; zero deviation from posted_prompt wording and implied constraints.

Scientific and Causal Correctness rubric:
level_1: No vertical growth of any kind appears at any crystal surface; the crystal(s) sit inert while the solution around them stays unchanged, or the solution only develops random, non-directional cloudiness with nothing resembling a rising column or tube.
level_2: A cloud-like or blob-like precipitate forms near a crystal, but it spreads outward and downward rather than rising as a narrow column, and no distinct membrane skin or tube wall forms on the crystal's surface; any growth present has no clear upward direction.
level_3: A narrow, tube-shaped column of precipitate visibly rises from the surface of at least one crystal, clearly distinguishable in color or opacity from the surrounding clear solution; the column continues growing upward during the clip rather than dissolving away, while the originating crystal stays anchored at the container floor.
level_4: The rising column keeps a continuous, unbroken tube shape as it lengthens, without collapsing into loose sediment or splitting into disconnected fragments; the solution outside the column stays visibly clear rather than turning cloudy; the crystal at the base keeps its original outline as the column grows above it.
level_5: The chimney-like column grows continuously and only upward, never drooping sideways or merging with a second column; its wall shows a visibly layered or porous texture consistent with a precipitate membrane rather than a solid opaque rod; no new columns start elsewhere in the solution; the originating crystal remains visually unchanged in size and shape at the base for the whole clip, consistent with growth being driven by fluid passing through the membrane rather than the crystal itself dissolving away.

Spatiotemporal Consistency rubric:
level_1: Container teleports or changes size/shape mid-video; liquid surface jumps or flickers discontinuously; crystals vanish/reappear; lighting shifts abruptly (e.g., full shadow → full highlight) without cause; structural breaks in container wall or liquid meniscus occur.
level_2: Container remains fixed but exhibits visible warping or perspective distortion; liquid surface shows inconsistent meniscus curvature across frames; crystals shift position without physical cause (e.g., slide sideways without flow); light/shadow on crystals changes discontinuously between frames.
level_3: Container is stable and upright; liquid surface maintains continuous, smooth meniscus; crystals remain at bottom without sliding or rotating; lighting is consistent in direction and intensity; no object flickering, clipping, or interpenetration occurs.
level_4: Container is stable and upright; liquid surface maintains continuous, smooth meniscus; crystals remain fixed at bottom with no lateral or vertical drift; lighting is consistent in direction, intensity, and softness; no temporal glitches (e.g., frame duplication, jump cuts, stutter) affect perception of stillness or growth.
level_5: Container is stable and upright with no micro-vibration or pixel-level jitter; liquid surface maintains perfectly continuous, smooth meniscus with no shimmer or noise; crystals are pixel-locked at bottom with zero sub-pixel displacement across all frames; lighting is fully consistent in direction, intensity, softness, and cast-shadow alignment; zero spatiotemporal artifact: no aliasing, no motion blur inconsistency, no depth misalignment.