Domain: Healthcare — Pharmaceutical Chemistry
Target concept: Sodium Penicillin Assay

Video generation prompt: An appropriate amount of sodium penicillin sample was placed in a test tube, followed by the addition of an appropriate amount of dilute hydrochloric acid. The mixture was heated to boiling, and then the alkaline copper tartrate reagent was added. The image was captured continuously by directing the camera toward the test tube.

Evaluation guide:
(i) Target concept: Acid hydrolysis of β-lactam antibiotics enables redox detection via copper reduction.
Minimum mechanism: Penicillin must be hydrolyzed under heat+acid to open the β-lactam ring, rearranging to penicillenic acid and its further breakdown products (e.g., penicillamine/penilloaldehyde, which carry free thiol/aldehyde groups) → these degradation products act as the reducing agent for Cu²⁺ → form insoluble Cu₂O (brick-red) in the alkaline copper tartrate medium.
(ii)Storyline: [0–2s] White powder placed in upright test tube → [2–4s] Clear liquid (HCl) added, meniscus visible → [4–7s] Heating applied, sustained bubbling/steam emerges from tube mouth → [7–8s] Boiling ceases, tube held steady → [8–10s] Blue reagent poured in, followed instantly by brick-red precipitate nucleating and settling. Perspective: Fixed frontal close-up on tube only; no hands, labels, or background distractions; all visibility constrained to interior tube contents and immediate rim.

Manual:
Experimental Procedure
1. Place white crystalline sodium penicillin powder into a clean test tube.
2. Add dilute hydrochloric acid solution to the tube.
3. Heat the mixture to boiling (visible vigorous bubbling/steam).
4. After boiling, add alkaline copper tartrate reagent (deep blue solution).
Observation of Experimental Phenomena
A brick-red precipitate forms immediately upon reagent addition and settles at the bottom of the tube.
Summary of Experimental Principles
Sodium penicillin degrades under acidic conditions upon heating, rearranging to penicillenic acid and further breakdown products (e.g., penicillamine/penilloaldehyde) that carry free thiol/aldehyde groups; these reduce Cu²⁺ in the alkaline copper tartrate reagent to Cu₂O — a characteristic brick-red oxide precipitate used for identification.

Prompt Grounding rubric:
level_1: No test tube appears, no white sodium-penicillin powder is placed in it, no dilute hydrochloric acid is added, no heating step occurs, and no alkaline copper tartrate reagent is added; the camera does not hold a fixed view on a single tube.
level_2: A test tube or a reagent container appears, but none of the required actions happen in sequence (no powder placed into the tube, no acid added, no heating shown, no reagent added), and/or the camera view does not stay fixed on the tube.
level_3: The test tube holds a white powder (the sodium penicillin sample); dilute hydrochloric acid is visibly poured in; heating is shown (flame or hot plate under the tube, with bubbling or steam indicating boiling); the four steps occur in the correct order: powder, then acid, then heat, then reagent; the camera stays on the test tube throughout.
level_4: Everything in the 3-point level holds, and the alkaline copper tartrate reagent (a deep-blue liquid) is clearly poured in only after the boiling step; the reagent's container or pour is visually distinguishable from the acid step; nothing extraneous (gloved hands, extra tubes, on-screen labels) blocks the tube or breaks the single continuous shot; the camera holds a steady frontal framing with no pan, tilt, or zoom.
level_5: Everything in the 4-point level holds, and the sequence reads as one uninterrupted take: white powder first, then a clear liquid poured in (acid), then clearly visible boiling (vigorous bubbling or steady steam), then the deep-blue reagent added right after boiling stops, all within a single fixed shot centered on the test tube with no cut or reframing.

Scientific and Causal Correctness rubric:
level_1: The liquid in the tube never changes color at all, and there is no visible link between the heating step and what happens after the reagent is added: the final mixture still looks like the original colorless acid or the original blue reagent with no reaction.
level_2: A color change does happen, but it's the wrong one (e.g., the mixture turns green, yellow, or stays blue instead of forming a brick-red solid), or a red/orange solid appears without the tube ever having been heated to boiling, or before the acid step happens.
level_3: A brick-red precipitate appears in the tube, and it appears only after the alkaline copper tartrate reagent is added to the already-boiled mixture; no precipitate forms if the reagent hasn't been added yet, and none forms if the mixture was never boiled.
level_4: The brick-red precipitate forms only when both conditions are met: boiling has already happened and the reagent has just been added; the deep-blue color of the reagent does not linger unreacted, and the mixture doesn't turn brown-black or some other color afterward; the liquid above the settling solid stays see-through.
level_5: The brick-red precipitate appears quickly and evenly right after the reagent goes in, standing out sharply against the liquid; it looks like a grainy or fluffy solid rather than a smooth film or gel; essentially none of the reagent's original blue color remains visible in the liquid afterward; there's no unrelated cloudiness, floating debris, or bubbles competing with the precipitate for attention, and the whole sequence (powder dissolving under heat and acid, then the reagent triggering the red solid) reads as one coherent cause-and-effect chain.

Spatiotemporal Consistency rubric:
level_1: The test tube vanishes from view and comes back, or the powder appears to be both outside and inside the tube at once, or the reagent pours in from nowhere with no visible source, or the flame/heat source pops in or out abruptly, or the lighting or shadows jump suddenly without anything in the scene moving to cause it.
level_2: One clear break in continuity happens: the tube's position, size, or tilt changes noticeably between steps; steam is visible before any heat source appears under the tube; the reagent enters the frame from one side and then inexplicably from the opposite side; or the camera itself jerks or rotates partway through.
level_3: The test tube, heat source, and reagent all keep consistent size, position, and orientation relative to each other; the heat source stays under the same spot on the tube; steam rises steadily upward while boiling; the reagent pours in from a steady height without jumping around in the frame; nothing in the scene teleports or reshapes.
level_4: Everything in the 3-point level holds, and in addition the tube's glass thickness, the curve of the liquid surface, and its reflections stay physically believable and don't flicker or warp as the powder dissolves, the mixture boils, and the reagent is poured; there's no stutter or distortion during any of the pouring or bubbling.
level_5: The tube's cylindrical shape and rounded bottom stay consistent in every frame; the liquid level only changes because something was poured in or because steam is visibly leaving (it never rises or falls on its own); the steam flows upward smoothly and continuously; the brick-red precipitate builds up gradually from the bottom rather than popping into existence all at once; every motion (the pour, the bubbling, the solid settling) looks like it obeys gravity and momentum the way a real liquid and solid would.