Domain: Natural Science — Chemistry
Target concept: Decomposition of hydrogen peroxide in the presence of manganese dioxide versus the uncatalyzed reaction

Video generation prompt: Two identical transparent beakers are placed side by side, each containing hydrogen peroxide. Manganese dioxide is added only to the left beaker, while the right beaker remains unchanged, and the reaction is observed.

Evaluation guide:
(i) Target concept: Catalytic acceleration of a chemical reaction demonstrated via controlled contrast between identical systems differing by presence/absence of catalyst.
Minimum mechanism: Hydrogen peroxide must be metastable under ambient conditions; manganese dioxide must be chemically inert yet provide active surface for bond cleavage; oxygen gas must form as discrete bubbles due to low solubility and density difference, all requiring intact molecular identity, phase stability, and interfacial physics.
(ii)Storyline: Frame 1–2: Static wide shot showing two identical transparent beakers side-by-side, both filled with still, colorless liquid. Frame 3–4: Hand introduces dark granular solid exclusively into left beaker; solid makes unambiguous contact with liquid surface. Frame 5–10: Left beaker exhibits continuous, upward-rising stream of spherical bubbles originating from solid-liquid interface; right beaker remains completely quiescent, with no bubble nucleation, surface ripple, or optical disturbance. Entire sequence viewed from fixed frontal perspective with consistent lighting and no occlusion.

Manual:
Experimental Procedure
1. Place two identical transparent beakers side-by-side on a flat surface.
2. Fill both beakers with equal volumes of colorless hydrogen peroxide solution.
3. Add a small amount of black/brown manganese dioxide powder only to the left beaker.
Observation of Experimental Phenomena
- Left beaker: Immediate, continuous evolution of discrete, spherical, transparent bubbles rising steadily through liquid and accumulating at surface.
- Right beaker: No bubble formation, no surface disturbance, liquid remains still and clear throughout.
Summary of Experimental Principles
Manganese dioxide acts as a catalyst for hydrogen peroxide decomposition: 2H₂O₂ → 2H₂O + O₂↑. It lowers activation energy, enabling rapid O₂ gas evolution only where present — no reaction occurs in the uncatalyzed right beaker.

Prompt Grounding rubric:
level_1: Neither beaker is shown as clear/transparent, or only a single beaker appears instead of two; the two beakers are not placed next to each other; no hydrogen peroxide liquid is visible in either container; manganese dioxide is never shown being added to the left beaker; there is no depiction of an addition action at all.
level_2: Two transparent beakers appear next to each other, but at least one of the following is missing: hydrogen peroxide liquid visible in both, manganese dioxide added only to the left beaker, or a clear left/right distinction maintained throughout the sequence.
level_3: Two transparent beakers sit side by side, each holding a visible liquid consistent with hydrogen peroxide, and manganese dioxide is added only to the left one, matching the prompt's setup; however, either the beaker walls look distorted or opaque rather than clearly transparent, or the moment the powder touches the liquid surface is not clearly shown.
level_4: Everything in the 3-point level is correct and unambiguous: two matching transparent beakers side by side; clear liquid visible in both; dark granular manganese dioxide clearly added only to the left beaker with visible contact between the powder and the liquid surface; no extra objects or actions beyond the prompt. A minor flaw may remain, such as brief partial occlusion during the addition or a momentary flicker in brightness.
level_5: Full fidelity to the setup: two identical transparent beakers placed strictly side by side in a fixed frontal view; the liquid in both looks like clear water; the manganese dioxide powder is introduced only into the left beaker with immediate, visible contact and no spillage into the right beaker; there is no extra object, no camera movement, no occlusion, and no timing mismatch; every frame matches the scenario described in the prompt.

Scientific and Causal Correctness rubric:
level_1: No bubbling appears in either beaker; or vigorous bubbling appears in both beakers rather than only the left one; or bubbling appears only in the right beaker; or gas bubbles are already forming somewhere in the clip before any manganese dioxide has ever been added to either beaker, i.e. the reaction is underway with no catalyst having entered the scene at all; or the two beakers look identical in behavior throughout, with nothing distinguishing the catalyzed side from the uncatalyzed side.
level_2: Bubbling appears in only one beaker, but it is the wrong one (the right, untreated beaker); or the manganese dioxide is shown being added to the left beaker, but the bubbling starts a moment before the powder actually touches the liquid surface rather than right after; or the left beaker only shows swirling from the powder's impact rather than actual gas bubbles; or the liquid changes color in either beaker (hydrogen peroxide decomposition here should not produce a color change).
level_3: Bubbling appears only in the left beaker and only after the manganese dioxide is added, with the right beaker showing none; however, the bubbling in the left beaker looks weak or irregular (occasional froth or sluggish surface disturbance) rather than a steady stream of distinct round bubbles rising through the liquid.
level_4: Bubbling appears only in the left beaker, starts only once the manganese dioxide contacts the liquid, and shows a steady stream of distinct round bubbles rising continuously from the powder up to the surface; the right beaker stays completely still and bubble-free the whole time; neither beaker shows a color change, precipitate, or any sign of heating.
level_5: Everything in the 4-point level holds with no exceptions: the left beaker shows immediate, sustained, vigorous bubbling of clear round bubbles rising continuously from the powder to the surface; the right beaker shows absolutely no bubbles, ripples, or cloudiness at any point; both liquids stay colorless and clear; there is no unrelated artifact (fogging, splashing, or floating particles) that would suggest anything other than a straightforward catalyzed decomposition on the left and no reaction on the right.

Spatiotemporal Consistency rubric:
level_1: One or both beakers vanish and reappear; the manganese dioxide appears already inside the left beaker with no visible hand or motion adding it; the liquid level in either beaker changes with no visible cause; the lighting shifts abruptly (e.g., full shadow to full highlight) mid-sequence; or the view cuts abruptly between a close-up and a wide shot with no beaker staying in place across the cut.
level_2: The two beakers are no longer side by side (e.g., one overlaps, sits behind, or is angled more than about 30° relative to the other); the camera view rotates or pans during the sequence; the manganese dioxide appears to jump from the hand directly into the beaker with no visible falling motion; the liquid surface sits perfectly still and then suddenly ripples with no powder or motion shown causing it.
level_3: Both beakers stay in the same relative position and at the same size throughout, with no teleporting or breaking apart; minor flaws may remain, such as a brief flicker during the addition, a short, barely noticeable reflection glare passing over one beaker, or a slight shift in background objects that does not change the beakers' alignment to each other.
level_4: Everything in the 3-point level holds, and additionally: the camera viewpoint never moves; the liquid's ripple after the powder lands spreads outward in a physically plausible way; the manganese dioxide falls in a continuous downward path into the left beaker rather than skipping partway; the right beaker shows no vibration or motion of its own at any point.
level_5: Everything in the 4-point level holds, and additionally: the beakers' positions, sizes, and spacing relative to each other look identical from the first frame to the last; the manganese dioxide's fall is continuous and gravity-consistent, dispersing naturally on contact with the liquid; the bubbles rising in the left beaker move upward at a steady, continuous pace with no stutter or repeated frame; the right beaker shows no motion, no glare change, and no trembling at any point in the sequence.