Domain: Natural Science — Chemistry
Target concept: Hydrogen Peroxide Decomposition under Different Hydrogen Peroxide Concentrations and Oxygen Conditions

Video generation prompt: Two transparent flasks are placed side by side, one labeled with a blue mark and the other with a red mark, containing hydrogen peroxide solutions of different concentrations, each connected to a balloon; manganese dioxide catalyst was also added.

Evaluation guide:
(i) Target concept: Catalytic decomposition rate dependence on reactant concentration, visualized via gas volume displacement.
Minimum mechanism: Manganese dioxide must be present and in contact with H₂O₂ solution in both flasks; oxygen gas must be generated *in situ* and captured *exclusively* by the sealed balloon; differential balloon expansion must arise solely from differential O₂ production volume, not leakage, timing, or external pressure.
(ii)Storyline: Frame 1–2: Two empty transparent flasks placed side-by-side, labeled blue (left) and red (right). Frame 3–4: Liquids poured (identical appearance). Frame 5–6: Manganese dioxide added to both flasks (granular dark solid visible entering liquid). Frame 7–8: Balloons placed and sealed over openings (uninflated, taut fit). Frame 9–10: Balloons begin inflating, blue-flask balloon expands more continuously and reaches visibly larger final size. Viewpoint: Fixed frontal orthographic view, no occlusion, full visibility of both flasks, labels, balloons, and liquid levels throughout.

Manual:
Experimental Procedure
1. Place two identical transparent flasks side-by-side on a flat surface.
2. Label left flask with a clear blue mark; right flask with a clear red mark.
3. Pour hydrogen peroxide solution into both flasks (same volume, different concentrations — not visually distinguishable).
4. Add manganese dioxide catalyst simultaneously to both flasks.
5. Immediately seal each flask opening with an uninflated balloon.
Observation of Experimental Phenomena
- Both balloons inflate due to oxygen gas production.
- The balloon on the blue-labeled flask inflates to a larger size than the one on the red-labeled flask.
- No color change, boiling, or splashing occurs in either flask.
Summary of Experimental Principles
- Hydrogen peroxide decomposes into water and oxygen gas when catalyzed by manganese dioxide.
- Higher hydrogen peroxide concentration yields greater oxygen volume under identical catalyst and temperature conditions, causing greater balloon expansion.

Prompt Grounding rubric:
level_1: No two transparent flasks visible; no blue or red label present; no balloon attached to either flask; no manganese dioxide visibly added; no side-by-side spatial arrangement.
level_2: Two transparent flasks are present and side-by-side, but at least one label is missing or incorrect color (e.g., both blue, both red, or non-blue/non-red); or at least one balloon is absent or not connected to a flask; or manganese dioxide is not visually present in either flask.
level_3: Two transparent flasks are side-by-side; one has a clearly visible blue label, the other a clearly visible red label; both flasks contain liquid; both flasks have a balloon attached and sealed to the opening; manganese dioxide is visibly present inside both flasks (e.g., as dark granular solid settling or suspended).
level_4: All conditions for score 3 are satisfied, AND both flasks are identically shaped and proportioned; labels are centered on the same relative position on each flask; balloons are identical in shape, orientation, and attachment point; manganese dioxide appears only inside flasks (not on exterior or in air).
level_5: All conditions for score 4 are satisfied, AND labels are exclusively blue and red (no mixed hues, no text overlay ambiguity), AND no extraneous objects (e.g., hands, tools, background lab equipment) intrude into the frame; AND viewpoint is strictly frontal, fixed, and centered on the pair: no tilt, no zoom, no parallax shift.

Scientific and Causal Correctness rubric:
level_1: No observable gas evolution; no balloon inflation; no difference in balloon size between flasks; no visible reaction occurring in either flask.
level_2: At least one balloon inflates, but both inflate to identical size/shape; OR only one balloon inflates while the other remains completely deflated with no sign of gas production; OR inflation occurs before manganese dioxide addition is visible.
level_3: Both balloons inflate; one balloon is visibly larger than the other; the size difference emerges after manganese dioxide is visibly present in both flasks; no deflation or bursting occurs during video.
level_4: All conditions for score 3 are satisfied, AND the larger balloon corresponds to the flask with the blue label (or red label, but consistently aligned per posted_prompt intent: blue = higher concentration, red = lower concentration); AND no color change, precipitation, or phase separation occurs in either liquid beyond expected clarity.
level_5: All conditions for score 4 are satisfied, AND the size difference between balloons is continuous and monotonic (no reversal, no oscillation); AND no liquid splashing, overflow, or ejection from flask openings; AND manganese dioxide remains fully submerged in liquid throughout; AND both liquids remain transparent and colorless (no yellowing, bubbling at surface unrelated to balloon inflation).

Spatiotemporal Consistency rubric:
level_1: The two flasks jump to different positions, or one vanishes and reappears, between frames; a balloon appears fully inflated with no attachment shown in an earlier frame, or disappears entirely from the shot; the manganese dioxide granules jump to a different spot inside the flask or vanish from view without explanation; or the lighting on the scene abruptly switches between bright and dark, or the shadows suddenly jump to a different direction, with no visible cause.
level_2: At least one clear spatiotemporal break occurs: a balloon separates from its flask opening and reattaches in a later frame; a flask visibly rotates by more than roughly 15 degrees with no apparent cause; the blue or red label slides to a different spot on the flask, shifting by more than about a third of the flask's width, between frames; or the transparency of a flask's liquid, or the sheen on a balloon's surface, flickers on and off between frames with no corresponding change in the balloon's actual inflation state.
level_3: Both flasks stay in the same side-by-side positions and orientation for the entire video; both balloons remain sealed to their flask openings without detaching; the manganese dioxide granules stay inside their original flask; neither flask, balloon, nor label flickers, warps, or breaks apart at any point; the transparency of both flasks' liquid and the visibility of the manganese dioxide granules through the glass stay visually consistent from the first frame to the last, with no sudden fogging, glare, or unexplained opacity change.
level_4: In addition to the 3-point requirements: balloon inflation looks like a smooth, gradual expansion rather than an abrupt jump in size from one frame to the next; neither balloon nor flask appears stretched, squashed, or distorted in shape; the balloons never visibly pass through or overlap the glass walls of the flasks.
level_5: In addition to the 4-point requirements: the camera viewpoint looks completely fixed, with no visible drift in the flasks' position, no visible change in their size relative to each other, and no visible shift in how the labels line up on the flasks; both balloons' inflation only ever grows larger over time, with no visible shrinking or back-and-forth pulsing at any point.