Domain: Natural Science — Chemistry
Target concept: Copper sulfate is soluble in water but insoluble in oil during shaking and settling.

Video generation prompt: A transparent glass jar with water at the bottom and plant oil at the top was supplied with copper sulfate crystals. After shaking, it was left to settle.

Evaluation guide:
(i) Target concept: Immiscibility-driven selective solubility of ionic compounds in polar vs. nonpolar solvents.
Minimum mechanism: Water must be polar and capable of hydrating Cu²⁺ and SO₄²⁻ ions; plant oil must be nonpolar and incapable of solvating ions; jar geometry must allow gravity-driven phase separation; copper sulfate must exist as crystalline solid prior to dissolution.
(ii)Storyline: Frame 0–1: Static shot showing glass jar with two sharp horizontal layers, lower (water, colorless, denser), upper (oil, pale yellow, less dense), and blue crystals resting *on the water surface* (not floating in oil, not submerged in oil). Frame 2–3: Continuous shaking motion: crystals break apart, disperse, and transiently color both layers. Frame 4–10: Uninterrupted settling: layers separate progressively; blue color migrates downward and concentrates *only* in water; oil clears completely; final state shows crisp interface, homogeneous blue water, and fully transparent oil. Perspective: Fixed frontal view, no occlusion, full jar always in frame, lighting consistent, no text/labels.

Manual:
Experimental Procedure
1. Place copper sulfate crystals (blue solid) onto the water layer in a transparent glass jar containing water at the bottom and plant oil floating on top.
2. Shake the jar vigorously for ~2 seconds.
3. Set the jar down and observe for ~5 seconds as layers separate.
Observation of Experimental Phenomena
- Before shaking: blue crystals rest on colorless water; oil layer is colorless and transparent above.
- During shaking: blue particles disperse throughout the mixture.
- After settling: blue color is confined exclusively to the lower water layer; oil layer remains colorless and transparent; no blue color in oil.
Summary of Experimental Principles
Copper sulfate is soluble in water but insoluble in oil — thus it dissolves only in the aqueous phase, producing a blue solution, while remaining undissolved and invisible in the oil phase.

Prompt Grounding rubric:
level_1: No transparent glass jar visible; no water layer present; no plant oil layer present; no copper sulfate crystals shown at any time; no shaking action depicted; no settling phase shown.
level_2: A transparent container is present but not a glass jar (e.g., plastic beaker or opaque cup); either water or plant oil is present but not both in correct layered configuration; copper sulfate crystals are shown but not placed into the container before shaking; shaking or settling is missing entirely.
level_3: A transparent glass jar is present with two distinct horizontal layers: a lower layer and an upper layer; copper sulfate crystals are visibly placed into the jar before shaking; shaking action is depicted; settling phase is shown after shaking; however, at least one of the following is incorrect: (a) lower layer is not labeled/visually identifiable as water, (b) upper layer is not labeled/visually identifiable as plant oil, or (c) crystals are not placed *before* shaking.
level_4: Transparent glass jar is present; two immiscible liquid layers are clearly distinguishable by position and appearance: lower layer is colorless and fluid, upper layer is pale yellow/light amber and less dense; copper sulfate crystals (blue solid) are placed into the jar *before* shaking; shaking action is depicted; settling phase is shown; all steps occur in correct sequence; no extraneous objects or actions introduced.
level_5: All elements from score 4 are present *and* the copper sulfate crystals are placed directly onto the surface of the lower (water) layer *before shaking*, not suspended in air or embedded in oil; the jar remains stationary and upright throughout; viewpoint is fixed frontal; no cuts, zooms, or overlays; all objects maintain consistent size, shape, and relative spatial arrangement across all frames.

Scientific and Causal Correctness rubric:
level_1: Copper sulfate crystals dissolve in the upper (oil) layer; or remain undissolved in both layers after shaking and settling; or change to non-blue color; or water and oil layers mix permanently; or no color change occurs anywhere despite dissolution.
level_2: Crystals remain intact and blue in the oil layer after shaking and settling; or dissolve fully in oil; or dissolve only in oil and not in water; or water layer turns blue *before* shaking; or oil layer becomes colored during or after shaking.
level_3: After shaking, blue color appears *only* in the lower layer during settling; crystals disappear from view *only* in the lower layer; upper oil layer remains colorless and unchanged; however, blue color spreads into oil layer *during* shaking (transient mixing), or blue color persists in lower layer but crystals are still partially visible as solids after settling.
level_4: During shaking, blue particles disperse throughout the entire mixture; during settling, blue color concentrates *exclusively* in the lower layer and becomes uniformly distributed there; upper oil layer remains completely colorless and transparent throughout; crystals are no longer visible as discrete solids *only* in the lower layer after settling; no blue tint appears in oil at any time after full settling.
level_5: All conditions from score 4 are satisfied *and* blue color appears *only after* shaking begins (not before); blue color is absent in lower layer before shaking; after full settling, lower layer is homogeneously blue and transparent, upper layer is fully colorless and transparent, and no residual blue particles or streaks appear at the interface or within oil.

Spatiotemporal Consistency rubric:
level_1: Jar disappears/reappears; liquids teleport between positions; crystals vanish mid-air; shaking motion is discontinuous (jumps, freezes, skips); settling shows abrupt layer reformation without gradual separation.
level_2: Jar changes size/orientation without cause; oil and water layers swap vertical positions mid-video; crystals move laterally through glass wall; shaking motion lacks continuity (e.g., starts/stops abruptly with no acceleration/deceleration); settling shows instantaneous stratification with no observable transition.
level_3: Jar remains in fixed position and orientation; shaking shows continuous back-and-forth motion; settling shows gradual separation of layers over time; however, one of the following occurs: (a) light/shadow on jar changes abruptly between shaking and settling phases, (b) reflection pattern on jar surface discontinuously shifts, or (c) meniscus curvature changes inconsistently between phases.
level_4: Jar maintains constant size, position, and orientation; shaking motion is smooth and continuous with natural deceleration; settling shows progressive, unidirectional separation of layers with stable meniscus formation; lighting and shadow remain consistent across all phases; no object flickering, warping, or structural deformation.
level_5: All conditions from score 4 are satisfied *and* the interface between water and oil remains sharply defined *throughout* shaking (as transient emulsion) and re-emerges with identical curvature and sharpness after settling; no inter-frame jitter, pixelation, or motion blur that obscures layer boundaries or crystal visibility.