Domain: Natural Science — Chemistry
Target concept: Decomposition of hydrogen peroxide with and without a catalyst, producing oxygen bubbles

Video generation prompt: Two identical transparent flasks are placed side by side, each containing hydrogen peroxide and a balloon; a solid catalyst is added only to the left flask, and both are recorded without interference.

Evaluation guide:
(i) Target concept: Catalytic acceleration of H₂O₂ decomposition produces quantifiably more O₂ gas in real time, enabling visual discrimination via balloon inflation. Minimum mechanism: Catalyst must be heterogeneous (solid phase), chemically inert (no consumption), and kinetically effective (O₂ generation rate > diffusion + balloon compliance threshold) within observation window; H₂O₂ must remain liquid-phase and unstirred to isolate catalyst effect.
(ii)Storyline: [Frame 0] Static wide shot: two identical flasks side-by-side, both filled with clear liquid, both sealed with identical deflated balloons. [Frame ~1–2] Solid catalyst enters left flask and settles; no bubbles yet. [Frame ~3–4] First bubbles emerge continuously from left flask liquid surface. [Frame ~5–8] Left balloon expands steadily, maintaining seal and symmetry; right balloon remains inert. [Frame ~9–10] Left balloon sustains inflation; no reversal, leakage, or instability. Perspective: fixed frontal view, eye-level, centered on flask midlines; no occlusion; background neutral and static to ensure visibility of balloon shape change and bubble motion.

Manual:
Experimental Procedure
1. Place two identical transparent flasks side-by-side on a flat surface.
2. Fill each flask with equal volume of clear hydrogen peroxide solution.
3. Stretch and seal one balloon over the mouth of each flask.
4. Add a visible solid catalyst (e.g., manganese dioxide pellets) only into the left flask.
5. Record continuously from fixed frontal viewpoint for 10 seconds without interference.
Observation of Experimental Phenomena
- Left flask: continuous stream of oxygen bubbles rises from liquid surface; balloon inflates progressively and remains sealed.
- Right flask: no bubbles, no gas evolution, balloon remains fully deflated and unchanged.
Summary of Experimental Principles
Hydrogen peroxide decomposes slowly into water and oxygen; a solid catalyst accelerates this reaction without being consumed, producing observable oxygen gas that inflates the balloon. The uncatalyzed reaction is too slow to produce detectable gas in 10 seconds.

Prompt Grounding rubric:
level_1: No two transparent flasks appear side by side in view; balloons are missing from the flask mouths; no solid catalyst is visible entering either flask; the scene never shows both flasks together in one continuous shot.
level_2: Two flasks and two balloons appear, but the catalyst is missing from both flasks, or it is added to the right (should-be-inert) flask, or it looks like a dissolved liquid tint rather than a solid chunk; the flasks are not held in a fixed side-by-side view (e.g., one drifts out of frame or the camera cuts between them).
level_3: Two identical transparent flasks are shown together in one continuous shot, each holding clear hydrogen peroxide solution and capped with an intact balloon; a visibly solid, granular catalyst (e.g., manganese dioxide chips) is added only to the left flask; no third container, hand, or utensil remains in frame after the addition.
level_4: In addition to the level-3 setup, the catalyst is unmistakably a discrete solid piece (not a powder cloud or a dissolved tint) at the instant it enters the left flask, no pipette, spoon, or label lingers in the shot, and both balloons stay fully attached and undamaged for the whole recording.
level_5: In addition to the level-4 setup, the catalyst comes to rest and stays visibly settled at the bottom of the left flask (it does not float, dissolve, or disperse), the two flasks keep matching orientation and lighting exposure throughout, and the camera holds a single fixed framing with no zoom or refocus at any point.

Scientific and Causal Correctness rubric:
level_1: Neither flask shows oxygen bubbles forming at the liquid surface, and both balloons stay slack and unchanged; the video shows no sign that hydrogen peroxide is decomposing in either flask.
level_2: Bubbles form in both flasks together, or only in the untreated right flask; likewise, the right balloon inflates too, or only the right balloon inflates while the left stays flat, so the video gives no visual evidence that the solid catalyst is what drives the reaction.
level_3: Bubbles rise continuously and only from the left (catalyst-containing) flask while the right flask's liquid stays undisturbed; the left balloon visibly grows in volume as it fills, and the right balloon stays fully collapsed.
level_4: In addition to level 3, bubbling in the left flask starts only once the catalyst has actually touched the liquid (not before), the left balloon's inflation is one-directional (it never partially deflates and re-inflates), and the right flask shows no bubbling or balloon movement at any point in the recording.
level_5: In addition to level 4, the left flask shows a dense, steady stream of bubbles (not just an occasional isolated bubble), and the left balloon reaches a clearly larger, visibly taut size (at least twice its starting diameter) while remaining sealed; the right flask shows no surface disturbance or balloon change whatsoever, making the catalyzed/uncatalyzed contrast unambiguous to a viewer.

Spatiotemporal Consistency rubric:
level_1: The flasks or balloons vanish and reappear at a different position; the catalyst disappears mid-fall before reaching the liquid; a shadow or highlight jumps instantly between two entirely different lighting states; a flask's rim or the balloon's neck shows a visible break that appears and disappears across frames.
level_2: One flask or balloon blinks in and out across a handful of frames; the catalyst is shown mid-air and then, with no visible drop, is already resting in the liquid with no in-between contact moment; the left balloon jumps straight from fully deflated to half-inflated with no visible intermediate stretch.
level_3: Both flasks and balloons hold steady position, size, and orientation throughout; the catalyst's entry into the left flask is shown as one continuous falling-and-settling motion; the left balloon's inflation passes visibly through intermediate stages (slack, slightly rounded, then more inflated) rather than jumping between states; no object overlaps another inconsistently (e.g., the balloon never appears to incorrectly overlap or pass behind the flask's neck).
level_4: In addition to level 3, the light source and the flasks' cast shadows keep the same direction and softness throughout (no highlight suddenly relocating on the glass), the flasks keep their round cross-section without warping, and the rising bubbles move upward in a fairly straight path without sideways jumps or reversal.
level_5: In addition to level 4, the catalyst visibly touches the liquid before the first bubble appears, with bubbling starting within about 3 frames of contact (not several seconds of unexplained delay), and the left balloon's expansion continues at a steady, even pace without sudden speed-ups, stalls, or bubbles that appear to freeze mid-rise across several frames.