Domain: Natural Science — Chemistry
Target concept: The decomposition of hydrogen peroxide in a transparent flask, showing the relationship between the rate of bubble formation and concentration.

Video generation prompt: On the laboratory bench, three transparent flasks contain hydrogen peroxide of colorless, light blue, and dark blue, respectively, each with an equal amount of solid catalyst added.

Evaluation guide:
(i) Target concept: Visual demonstration of concentration-dependent reaction kinetics via controlled color-coded H₂O₂ solutions undergoing catalyzed decomposition.
Minimum mechanism: Catalyst must make direct physical contact with liquid; bubbling must originate *only* at catalyst–liquid interface; color variation must be stable (non-fading, non-mixing) and serve as a reliable proxy for relative concentration; no external agitation or heating applied.
(ii)Storyline: [Frame 0–1] Three empty transparent flasks placed side-by-side on bench; [Frame 2–3] Liquids poured: colorless → light blue → dark blue (or all pre-filled and identified); [Frame 4] Solid catalyst added to all three flasks (simultaneously or in strict left→middle→right order); [Frame 5–10] Bubbling initiates within 1–2 seconds post-contact in all flasks; bubbling intensity diverges progressively and stably: dark blue > light blue > colorless; all bubbles rise vertically; view remains fixed frontal, full-flask framing with no occlusion; lighting uniform and static.

Manual:
Experimental Procedure
1. Place three identical transparent flasks side-by-side on a laboratory bench.
2. Fill flask A with colorless hydrogen peroxide solution, flask B with light blue hydrogen peroxide solution, flask C with dark blue hydrogen peroxide solution.
3. Add identical amounts of solid catalyst (e.g., manganese dioxide) to each flask simultaneously.
Observation of Experimental Phenomena
- All three flasks produce oxygen gas bubbles at the catalyst surface.
- Bubble formation rate differs: darkest blue flask shows most vigorous bubbling, light blue shows moderate bubbling, colorless shows least bubbling.
Summary of Experimental Principles
- Hydrogen peroxide decomposes into water and oxygen gas: 2H2O2 -> 2H2O + O2.
- Pure H2O2 solutions are colorless regardless of concentration; here a safe blue tracer dye has been added in proportion to H2O2 concentration, so a darker blue visually stands in for a higher concentration, which in turn drives a faster catalyzed decomposition rate.

Prompt Grounding rubric:
level_1: Fewer than three flasks are shown, or none of the flasks show three visually distinct liquid colors (colorless, light blue, dark blue), or no solid catalyst appears in any flask, or the scene is not set on a lab bench.
level_2: At least one flask appears, but not all three; or all three are shown yet their liquids look the same color (e.g., all colorless); or none of the three has a solid catalyst added; or the flasks are stacked, scattered, or otherwise not placed next to each other on the bench.
level_3: Three flasks sit next to each other on the bench, each holding liquid, each with a visible piece of solid catalyst inside, but at least one pair of the three colors is hard to tell apart (e.g., the colorless and light-blue liquids look nearly identical, or light blue and dark blue blend together).
level_4: Three flasks sit next to each other on the bench, catalyst is visible in each, and the three liquid colors are clearly distinguishable and correctly assigned: one is colorless, one is light blue, one is dark blue, with no color swapped into the wrong flask; all three flasks stand upright, intact, and unobstructed.
level_5: Everything required for score 4 holds, AND the left-middle-right order of the three flasks never changes across the clip (no flask is shown moved, rotated, or blocked from view at any point), and all three keep the same size, tilt, and spacing relative to each other for the entire video.

Scientific and Causal Correctness rubric:
level_1: No flask produces bubbles at all; or all three flasks bubble identically regardless of liquid color; or bubbles appear before the catalyst touches the liquid; or bubbles appear in a flask that has no catalyst in it.
level_2: Bubbling shows up in only one or two of the three flasks; or all three start bubbling at the same moment with the same strength and duration, showing no difference between them; or the strongest bubbling appears in the colorless flask, which runs opposite to the expected trend.
level_3: All three flasks bubble, and the bubbling strength clearly differs between at least two of them, but the ranking runs backward: for example the colorless flask bubbles hardest while the dark blue flask bubbles weakest, the opposite of what higher H2O2 concentration should produce.
level_4: All three flasks bubble at different, clearly ranked strengths (the dark blue flask bubbles most vigorously, the light blue flask bubbles at an intermediate rate, and the colorless flask bubbles the least), and this ranking holds for as long as the reaction is shown, without the order flipping partway through; no bubbling comes from outside the liquid or from the catalyst sitting dry.
level_5: Everything required for score 4 holds, AND the dark-blue-more-than-light-blue-more-than-colorless ranking holds at every single moment shown, with no frame where two flasks look equally vigorous, and none of the three flasks stops bubbling and restarts in a way that would contradict a smooth, continuous catalyzed decomposition.

Spatiotemporal Consistency rubric:
level_1: A flask's position or the catalyst inside it changes with no visible motion connecting the before and after; the liquid level jumps up or down with no cause; the background or lighting flashes or cuts sharply; a flask's transparency changes abruptly (clear one moment, opaque the next).
level_2: At least one flask visibly bends, stretches, or warps out of its normal cylindrical shape; catalyst grains appear to float upward before ever touching the liquid, or sink implausibly fast; bubbles drift sideways or downward in several frames instead of rising; the lighting on the three flasks changes abruptly partway through the clip.
level_3: All three flasks stay rigid and stay in place; the catalyst stays fully submerged once it settles into each flask; bubbles rise straight up in every flask; each liquid surface stays flat and level; the lighting looks the same across all three flasks and across the clip. Aside from a small amount of frame-to-frame jitter or slight softness in focus, nothing breaks the sense that this is one continuous event.
level_4: Everything required for score 3 holds, AND bubbles only ever start at the catalyst's surface and rise the whole way up without abruptly vanishing mid-rise; the camera's position relative to the three flasks never shifts, so there's no parallax mismatch between them; the shadows the three flasks cast agree with a single, shared light source.
level_5: Everything required for score 4 holds, AND in every flask the bubbling starts the instant its catalyst is added, with no delay; if the catalyst is added to the three flasks one after another, the bubbling begins in that same order; if added all at once, bubbling begins in all three at essentially the same moment; no frame appears dropped, repeated, or played out of order.