Domain: Natural Science — Chemistry
Target concept: Ethanol dissolves oil-based marker ink on glass more rapidly than water.

Video generation prompt: On a glass surface with oil-based marker scratches, place an ethanol pipette on the left and a blue-dyed water pipette on the right, release equal volumes of droplets, then wipe the left side with a cotton swab and wipe the right side with a separate, fresh cotton swab.

Evaluation guide:
(i) Target concept: Differential solubility of oil-based ink in polar vs. less-polar solvents.
Minimum mechanism: Oil-based ink must be hydrophobic and soluble in ethanol but insoluble in water; ethanol must wet and penetrate ink layer; water must bead and fail to disrupt ink adhesion; wiping must transfer dissolved ink away on ethanol side only.
(ii)Storyline: [0–2s] Static wide shot: glass with visible oil-based scratches, ethanol pipette left / blue-water pipette right. [2–3s] Synchronized droplet release: both land on scratches. [3–4s] 1-second dwell: ethanol droplet spreads visibly; water droplet beads. [4–6s] A first cotton swab wipes the left side; scratches fade in real time; that swab is then set aside. [6–8s] A second, separate cotton swab wipes the right side; scratches persist unchanged. [8–10s] Final static frame showing stark side-by-side contrast. Perspective: fixed frontal, eye-level, full glass + both pipettes + both wipe zones continuously in frame; no occlusion; scratches must remain legible throughout.

Manual:
Experimental Procedure
1. Place clean glass slide with fresh oil-based marker scratches horizontally.
2. Position ethanol-filled pipette on left side, blue-dyed water-filled pipette on right side.
3. Simultaneously release one droplet from each pipette onto respective scratch zones.
4. After 1 second contact, wipe the left side with a cotton swab, set that swab aside, then wipe the right side with a second, separate cotton swab.
Observation of Experimental Phenomena
Ethanol side: scratches rapidly fade or vanish during wiping. Water side: scratches remain fully visible and unchanged after wiping.
Summary of Experimental Principles
Ethanol dissolves oil-based marker ink on glass more rapidly than water due to ethanol’s lower polarity and higher solubility for non-polar organic compounds.

Prompt Grounding rubric:
level_1: No glass surface visible; no oil-based marker scratches present; no ethanol pipette on left; no blue-dyed water pipette on right; no droplet release action shown; no cotton swab wiping action shown.
level_2: Glass surface is present and shows scratches, but scratches are not oil-based (e.g., pencil, chalk, or ink visibly water-soluble); at least one pipette is present but incorrectly positioned (e.g., ethanol on right or water on left); droplets are released but not from pipettes; cotton swab appears but does not contact either side.
level_3: Glass surface with visible scratches is present; ethanol pipette is placed on the left and blue-dyed water pipette on the right; equal-volume droplets are released from both pipettes onto the scratched glass; both sides are wiped, but a single cotton swab is reused for both sides instead of two separate swabs, or wiping occurs before droplet contact, or the two wiping actions are not clearly sequential (left side first, then right side).
level_4: All prompt elements present and correctly arranged: glass surface with oil-based marker scratches; ethanol pipette on left, blue-dyed water pipette on right; droplets released synchronously from both pipettes onto scratches; a first cotton swab wipes the left side and is then clearly set aside out of the active wiping area, after which a second, visually distinct cotton swab wipes the right side, but spatial framing omits full side-by-side view (e.g., camera pans or cuts), or one droplet visibly splashes outside its scratch zone.
level_5: All prompt elements present, correctly arranged, and continuously visible in fixed side-by-side framing: glass surface with distinct oil-based marker scratches; ethanol pipette fully visible on left, blue-dyed water pipette fully visible on right; two droplets released simultaneously onto respective scratch zones; a first cotton swab makes one continuous wiping motion on the left side and is fully set aside before a second, separate cotton swab enters frame and makes one continuous wiping motion on the right side; both swabs and both wiping actions fully visible, no occlusion, no cut, no pan, no zoom.

Scientific and Causal Correctness rubric:
level_1: No dissolution observed on either side; both sides appear identical before and after wiping; scratches remain fully intact after wiping; droplets show no interaction with scratches (e.g., bead up uniformly or vanish instantly).
level_2: Dissolution occurs on only one side, but side is incorrect (e.g., blue-dyed water side shows removal while ethanol side does not); or dissolution appears on both sides equally; or color change occurs without removal (e.g., blue dye spreads but scratches remain unchanged).
level_3: Dissolution is visible on the ethanol side (scratches visibly fade or disappear during/after wiping), and no dissolution is visible on the blue-dyed water side (scratches remain fully intact after wiping); however, the blue dye in the water droplet is only faintly tinted rather than clearly blue, making the two droplets harder to tell apart at a glance, or a faint haze briefly appears on the glass that does not affect which side loses its scratches.
level_4: Ethanol side shows clear dissolution (scratches fade/disappear during or after wiping); blue-dyed water side shows no dissolution (scratches remain fully visible after wiping); ethanol droplet is colorless and spreads visibly across the scratch; blue-dyed water droplet is distinctly blue and beads up or spreads minimally, but one of: (a) wiping begins before the droplet fully contacts the scratch, or (b) residual blue dye smears across the water-side scratch without actually removing it, creating a false impression of interaction.
level_5: Ethanol side shows complete or near-complete removal of the oil-based marker scratches during/after wiping, with no residual streaks or pigment; blue-dyed water side shows zero removal: scratches remain sharp, unaltered, and fully visible after wiping; ethanol droplet is colorless and visibly wets the scratch zone; blue-dyed water droplet is vividly blue and remains beaded or only slightly spread; wiping directly follows droplet contact on each side, and the result is an unambiguous contrast between the two sides.

Spatiotemporal Consistency rubric:
level_1: Severe spatiotemporal violations: glass surface changes position/orientation between shots; pipettes teleport; droplets appear without release motion; cotton swab appears/disappears abruptly; lighting shifts drastically mid-sequence; scratches flicker or morph in shape.
level_2: Moderate violations: pipettes shift position between droplet release and wiping; cotton swab moves discontinuously (jumps between positions); droplet release and wiping occur in inconsistent temporal order (e.g., wiping precedes release in one side only); scratches visibly warp or distort during wiping.
level_3: Minor but detectable violations: slight camera jitter during the wiping motion; the ethanol droplet spreads across its scratch with an unnaturally abrupt burst of speed; the cotton swab's tilt or contact angle changes inconsistently between the two sides; the reflected light on the glass shifts subtly but continuously across the sequence, with no abrupt jump in the glass's highlight or in the pipettes' shadows.
level_4: All objects maintain consistent spatial relationships throughout: the pipettes remain fixed relative to the glass; both droplets originate from the pipette tips and land within their respective scratch zones; a first cotton swab moves smoothly and continuously across the left side and is clearly set aside before a second, separate cotton swab moves smoothly and continuously across the right side; no lighting flash, shadow jump, or perspective warp, but one brief, visible stutter in a swab's motion, or a momentary soft-focus blur during the wiping, keeps this short of full marks.
level_5: Zero spatiotemporal artifacts: the glass, both pipettes, both droplets, and both swabs hold fixed relative positions except when actively moving as described; all motion is smooth, continuous, and physically plausible; the light reflecting off the glass and the shadows cast by the pipettes and swabs do not shift in direction or brightness at any point; no frame drop, warp, stretch, or occlusion-induced discontinuity occurs; the first swab completes its full left-side wipe and is set fully aside before the second, separate swab begins its right-side wipe, both proceeding at a uniform speed and direction.