Domain: Natural Science — Chemistry
Target concept: Glucose decolorizes bromine water

Video generation prompt: A test tube contains an appropriate amount of bromine water solution. An appropriate amount of glucose solution is added to the solution in the test tube.

Evaluation guide:
(i) Target concept: Reductive decolorization of bromine water by glucose via electron transfer.
Minimum mechanism: Bromine water must be present as dissolved Br₂ (orange-brown); glucose must be in aqueous solution; contact must occur to enable redox reaction; product Br⁻ is colorless and remains dissolved; no catalyst or heat required under standard conditions.
(ii)Storyline: [Frame 0–2] Static shot: test tube centered, filled with homogeneous orange-brown liquid (bromine water); adjacent container holds colorless liquid (glucose solution). [Frame 3–5] Glucose solution is delivered into test tube via controlled transfer (e.g., dropper/pipette tip enters frame and dispenses). [Frame 6–8] Orange-brown hue visibly recedes uniformly from top to bottom or throughout volume; no bubbling or precipitation. [Frame 9–10] Final state: fully colorless, homogeneous liquid in test tube; no residual tint, no interface anomalies. Perspective: fixed frontal macro view; full test tube always in frame; no occlusion of liquid column during critical transition.

Manual:
Experimental Procedure
1. A test tube holds orange-brown bromine water.
2. Colorless glucose solution is added to the test tube.
Observation of Experimental Phenomena
The orange-brown color of bromine water fades completely, resulting in a colorless solution.
Summary of Experimental Principles
Glucose reduces bromine (Br₂) to colorless bromide ions (Br⁻), decolorizing bromine water — a characteristic test for reducing sugars.

Prompt Grounding rubric:
level_1: No test tube appears; no orange-brown bromine water is shown; no glucose solution is shown; no addition/transfer action takes place; none of these required elements from the posted prompt appear anywhere in the clip.
level_2: A test tube is shown, but bromine water is missing or shown as a clear (not orange-brown) liquid; the glucose solution is missing or never shown being poured or dropped in; or an addition action happens but targets the wrong container.
level_3: The test tube holds an orange-brown liquid consistent with bromine water; a second, colorless liquid (the glucose solution) is visible in a separate container; the glucose solution is shown being transferred into the test tube; test tube, bromine water, and glucose solution are all present and the transfer connects them correctly.
level_4: Everything required for score 3 holds, and in addition the test tube and the glucose-solution container stay in the same relative spot next to each other throughout the shot or across a clean cut, the transfer happens without either container appearing to jump position, and nothing else blocks the view of the test tube while the glucose solution is being added.
level_5: Everything required for score 4 holds, and in addition the glucose solution is clearly directed into the test tube with no spill outside it or misaligned pipette/dropper tip, the test tube stays put and fully visible before, during, and right after the addition, and the camera holds one fixed angle with no pan, zoom, or rotation for the whole clip.

Scientific and Causal Correctness rubric:
level_1: The orange-brown color of the bromine water never fades during the clip; or it turns into some other hue (blue, green, purple); or a decolorization-like change appears before the glucose solution is ever added.
level_2: A color change happens, but it doesn't match a glucose–bromine reaction: fading is patchy rather than even, a cloudy precipitate appears, or the color shifts toward yellow/orange rather than disappearing entirely; or the color loss happens with no addition action shown beforehand.
level_3: The orange-brown bromine water is clearly visible before the glucose solution is added; after the addition, the liquid in the test tube turns uniformly colorless (or nearly indistinguishable from water); the color loss is confined to the test tube and only starts once the glucose solution has entered it.
level_4: Everything required for score 3 holds, and in addition the color fades gradually rather than switching instantly, the whole liquid volume loses color evenly with no patches of lingering orange-brown, and nothing else (bubbling, visible heating, a second layer forming) accompanies the change.
level_5: Everything required for score 4 holds, and in addition no trace of the orange-brown color remains anywhere in the solution, the colorless state holds steady rather than reappearing later, and the finished liquid looks like plain water or dilute glucose solution under the same lighting, with no odd tint from lighting effects.

Spatiotemporal Consistency rubric:
level_1: The test tube vanishes and reappears, or the liquid jumps to a different level between frames; the tube's lighting or shadow flips suddenly with no matching motion; the container warps or spins in a way that doesn't match how it was moving; or the clip cuts between shots that don't match in scale or angle.
level_2: The test tube shifts to a new spot with no visible path getting there; the liquid surface flickers or ripples in ways that don't hold together; the hand and the liquid stream fall out of sync (e.g., the dropper pulls away before liquid has finished leaving it); or the brightness in the shot suddenly jumps partway through for no clear reason.
level_3: The test tube keeps the same place and tilt throughout; the liquid surface stays level and behaves coherently; the glucose solution travels smoothly from its container into the test tube; the tube's shadow keeps a steady direction and strength; there's no frame skip that makes the liquid appear to jump.
level_4: Everything required for score 3 holds, and in addition the dropper or pipette moves at a natural speed and arc, the liquid stream flows as one continuous ribbon rather than breaking into fragments, the meniscus settles smoothly once the two liquids touch, and the tube's edges never tear, ghost, or shimmer in a way that breaks the sense of a solid object.
level_5: Everything required for score 4 holds, and in addition the camera and the test tube itself hold steady with no visible shake, the background and foreground move together in a way that looks physically consistent, the liquid surface where the glucose solution meets the bromine water looks optically right rather than warped, and the whole sequence (approach, contact, mixing, color loss) reads as one continuous cause-and-effect chain.