Domain: Healthcare — Nutrition and Food Hygiene
Target concept: Acrylamide Detection

Video generation prompt: A 10 mL extract of acrylamide-containing fried food was placed in a test tube. Potassium bromide-potassium bromate solution and rosaniline sulfite reagent were added. The test tube was heated in a 40°C water bath, and continuous photographs were taken with the camera aligned with the test tube.

Evaluation guide:
(i) Target concept: Bromination-based screening for acrylamide, in which bromine generated from potassium bromate and potassium bromide reacts with acrylamide's carbon-carbon double bond, and any bromine left over after that reaction brominates the rosaniline sulfite reagent into a magenta-colored product.
Minimum mechanism: Potassium bromate and potassium bromide must first react under heat to generate free bromine; this bromine adds across acrylamide's C=C double bond in the extract, consuming bromine in the process; once the rosaniline sulfite reagent is added, any bromine not consumed by acrylamide brominates the reagent's reduced, colorless form and generates its magenta color; because bromine generation and the color-forming reaction both depend on the 40°C water bath, no magenta color should appear before heating begins.
(ii)Storyline: [Frame 0–2] Test tube with pale yellow extract centered in view; [Frame 3–4] First reagent (potassium bromide-potassium bromate solution) dispensed into tube: liquid level rises, no color change; [Frame 5–6] Second reagent (rosaniline sulfite reagent) dispensed: liquid level rises further, still no color; [Frame 7] Tube placed into water bath: bath surface stable, tube fully immersed; [Frame 8–10] Magenta color emerges uniformly from bottom upward, intensifying continuously while tube remains motionless and fully in bath; camera remains fixed, frontal, and focused on tube mid-section throughout: no occlusion, no angle shift, no lighting fluctuation.

Manual:
Experimental Procedure
1. Place 10 mL extract of acrylamide-containing fried food into a clean test tube.
2. Add potassium bromide-potassium bromate solution, then rosaniline sulfite reagent.
3. Insert test tube into 40°C water bath and maintain for duration.
4. Capture continuous frontal photographs aligned with test tube axis.
Observation of Experimental Phenomena
Liquid in test tube develops a uniform magenta color exclusively during heating, only after both reagents are added.
Summary of Experimental Principles
Potassium bromate and potassium bromide react under heat to generate free bromine in situ; this bromine adds across the carbon-carbon double bond of acrylamide, consuming bromine as it does so. Bromine left over after that reaction brominates the rosaniline sulfite reagent, converting it from its colorless/reduced form to a magenta-colored product — a bromination-endpoint color change used in classical bromate-bromide analytical methods for unsaturated organic compounds. The depth of magenta that develops therefore reflects how much bromine remained unconsumed after reacting with the acrylamide present.

Prompt Grounding rubric:
level_1: No test tube present; no fried food extract visible; no potassium bromide-potassium bromate solution or rosaniline sulfite reagent shown; no water bath apparatus; no camera alignment with test tube; none of the listed steps depicted.
level_2: At least one correct object present (e.g., a test tube OR a liquid-filled container), but no identifiable fried food extract, no reagents added, no water bath scene, and no fixed frontal camera viewpoint aligned with test tube.
level_3: Test tube is present and contains a clear or pale yellow liquid (representing 10 mL extract); two distinct reagent bottles are visible beside it (one labeled/visually consistent with KBr-KBrO₃, one with rosaniline sulfite reagent); test tube is placed inside a water bath container set at ~40°C (indicated by label or thermal visual cue like mild steam or uniform ambient warmth); camera viewpoint is fixed and frontally aligned with test tube axis throughout.
level_4: All elements of 3-score are present AND reagents are visibly dispensed into the test tube (liquid streams or droplets entering tube); heating is ongoing (water bath shows gentle convection or stable thermal surface); camera remains rigidly aligned with test tube centerline without pan/tilt/zoom; no extraneous objects occlude test tube or reagent bottles.
level_5: All elements of 4-score are present AND reagent addition occurs in correct sequence: potassium bromide-potassium bromate solution added first, then rosaniline sulfite reagent added second; both additions are fully visible as discrete events; test tube remains upright and stationary during all additions and heating; camera viewpoint is unbroken, centered on test tube mid-height, showing full tube length and meniscus; no frame drop, cut, or perspective shift.

Scientific and Causal Correctness rubric:
level_1: No color change occurs; liquid remains colorless or unchanged throughout; no heating effect visible; no causal link between reagent addition and any observable phenomenon.
level_2: Color change appears but is inconsistent with the bromination-indicator chemistry: e.g., immediate pink without heating, a green/blue/purple hue instead of pink, or a color change that occurs before both reagents have been added.
level_3: Liquid in test tube transitions from colorless/pale yellow to pink only after both reagents are added AND while test tube is inside the water bath; no color change occurs before heating begins or after removal.
level_4: All elements of 3-score are satisfied AND color development is continuous and progressive (no abrupt flash or discontinuous jump); final color is uniformly distributed within liquid column (no layering, streaking, or sedimentation); no competing false-positive hues (e.g., orange, brown, or violet) appear.
level_5: All elements of 4-score are satisfied AND the pink color appears exclusively during heating and intensifies steadily over time (visibly deepening in saturation without fading or shifting); color is homogeneous across the entire liquid volume; no discoloration of tube walls, meniscus distortion, or precipitation; the hue matches the pink-to-magenta appearance typical of the brominated rosaniline dye, not orange, brown, or violet.

Spatiotemporal Consistency rubric:
level_1: The test tube abruptly relocates or changes size between frames instead of being carried by a visible hand or stand; the KBr-KBrO₃ or rosaniline sulfite reagent appears inside the tube with no visible pouring or dispensing motion; the water bath vanishes from the shot and then reappears; the camera view jumps to a different position or angle without a pan; the light on the tube and reagent bottles switches from one side to the opposite side within a single cut, with no corresponding change in camera or object position to justify it.
level_2: Major spatiotemporal breaks occur: the test tube's tilt changes by more than about 15 degrees and then snaps back upright without a smooth transition; the liquid level inside the tube jumps higher with no visible reagent entering; a reagent bottle drifts out of frame and returns showing a different fill level than before it left; the shadows cast by the test tube or reagent bottles flicker or switch sides inconsistently between neighboring frames.
level_3: The test tube stays in the same position and upright orientation throughout; the two reagent bottles (KBr-KBrO₃ and rosaniline sulfite reagent) remain stationary on the same surface; the water bath's surface stays level and continuous; the camera holds a single locked framing on the tube with no pan, tilt, zoom, or roll; the shadow cast by the test tube onto the bench or water bath stays on the same side and length from one frame to the next as reagents are added; the liquid meniscus rises and settles smoothly during each addition rather than snapping to a new level.
level_4: All 3-point conditions hold, and in addition each reagent's delivery follows a physically plausible downward path into the tube, with the liquid surface rising continuously as it is added rather than jumping in steps; no reagent bottle, pipette, or the tube itself floats, hovers, or shows unnatural buoyancy; the tube and bottles show no tearing, warping, or ghosting as the camera holds its framing through the addition and heating stages.
level_5: All 4-point conditions hold, and in addition the sequence of events stays strictly ordered and connected: the KBr-KBrO₃ solution is added and settles before rosaniline sulfite reagent is added, heating begins only once the tube is fully seated in the water bath, and any pink coloration first appears only after the tube has been in the bath for a visible interval, not before; no frame is duplicated, skipped, or frozen; the pipette or dispensing tool decelerates smoothly as it approaches the tube mouth, and the liquid surface's minor ripple after each addition settles out naturally rather than stopping abruptly.