Domain: Healthcare — Pharmaceutical Chemistry
Target concept: Fluconazole Assay

Video generation prompt: Accurately weigh an appropriate amount of fluconazole sample and place it in a dry test tube. Add 2 mL of concentrated sulfuric acid, and gently rotate the test tube to ensure complete dissolution of the sample. Observe the color and physical state of the solution.

Evaluation guide:
Target concept: Fluconazole identity verification via its characteristic chromogenic reaction with concentrated sulfuric acid, grounded in the acid-induced electronic transition of the triazole moiety. Minimum mechanistic assumption: Protonation/sulfonation of fluconazole under anhydrous strong acid conditions generates a stable, conjugated cationic chromophore absorbing at ~420–480 nm, yielding amber-brown color. Expected phased storyline: (1) Baseline: dry tube + white crystalline powder → (2) Perturbation: precise 2 mL conc. H₂SO₄ addition → (3) Activation: gentle rotation enabling complete dissolution without splashing or thermal artifact → (4) Emergence: rapid (≤4 s), uniform development of clear, transparent amber-brown solution → (5) Verification: sustained stability of color/clarity for ≥2 s under neutral lighting. Visibility constraints: Camera must frame tube mid-column (excluding top meniscus distortion and bottom curvature), with shallow depth-of-field focusing sharply on solution interior; lighting must be diffuse, front-lit, and spectrally neutral to enable unambiguous hue discrimination (amber-brown vs. yellow/brown/red).

Manual:
I. Basic Demonstration Information
Demonstration Title: Fluconazole Assay via Concentrated Sulfuric Acid Chromogenic Reaction
Subject: Healthcare - Pharmaceutical Chemistry - Fluconazole Assay
Demonstration Purpose: To visually demonstrate the characteristic amber-brown color development when fluconazole dissolves in concentrated sulfuric acid — a qualitative identification step in pharmaceutical analysis; to train accurate observation of solution color and physical state as diagnostic features; to reinforce safe, precise handling of corrosive reagents.
II. Demonstration Carrier/Equipment
Core Carrier: Pure fluconazole reference standard (white crystalline powder, USP grade); concentrated sulfuric acid (95–98%, analytical grade); dry 12×75 mm borosilicate test tube.
Auxiliary Equipment: Analytical balance (0.0001 g precision, displayed off-screen but implied by 'accurately weighed'); calibrated 2 mL glass syringe with clear graduation marks; lab bench with non-reflective black mat; neutral white LED lighting (5000 K, CRI >90); timer (for video pacing).
III. Demonstration Content Description
Layout: Test tube centered on bench; hand enters frame from lower right with pre-weighed fluconazole (visible as fine white crystals); powder is carefully deposited into dry tube; hand exits, re-enters with syringe containing exactly 2.0 mL acid (meniscus aligned with 2 mL mark); acid dispensed vertically into tube center; hand grasps tube near base and rotates gently 360° clockwise over 5 s; tube held vertically and motionless for ≥2 s for observation.
State Control: No heating, no stirring rod, no secondary reagents; dissolution must occur solely via acid contact and rotation; solution must be clear, homogeneous, and free of particulates or gas bubbles.
IV. Observation of Core Phenomena
Initial State: Dry test tube containing only white, free-flowing crystalline fluconazole powder (no clumps, no moisture).
Transition Event: Upon acid addition and rotation, crystals dissolve completely within 3–4 s; no effervescence, no smoke, no temperature-induced shimmer.
Final State: Clear, transparent, viscous amber-brown solution — a medium amber-brown color, with high gloss and no turbidity; physical state is homogeneous liquid (no phase separation, no sediment, no oil droplets).
Visual Verification Features: (1) Color: distinct amber-brown (not yellow, not red, not black); (2) Clarity: fully transparent (text behind tube legible); (3) Homogeneity: uniform hue and brightness top-to-bottom; (4) Surface: convex meniscus, no foam or film.
V. Summary of Key Knowledge Points and Principles
Core Concept Definition: Fluconazole assay using concentrated H₂SO₄ relies on acid-catalyzed protonation and potential sulfonation of the triazole ring, generating conjugated chromophores that absorb visible light — yielding a reproducible amber-brown color used as a qualitative color/identification test for the compound, distinct from quantitative assay methods such as chromatography.
Scientific Significance: This color reaction is specific to intact 1,2,4-triazole structure; degradation (e.g., hydrolysis) abolishes the response — thus serving both identification and purity screening. The absence of gas, heat, or charring confirms proper technique and sample integrity.
VI. Demonstration Precautions
Reagent Safety: Concentrated H₂SO₄ must be handled with nitrile gloves and eye protection (implied in professional context); no skin contact visible.
Sample Integrity: Fluconazole must be anhydrous — hydrated forms may yield paler or delayed color; tube must be dry to prevent dilution or side reactions.
Observation Fidelity: Lighting must be neutral white (no yellow/orange bias) to avoid hue misinterpretation; camera focus must be sharp on solution column (not tube wall or meniscus edge) to resolve true color and clarity.

Prompt Grounding rubric:
level_1: No test tube is shown; no white powder sample is placed in it; no sulfuric acid is added; no rotating or swirling motion occurs; there is no view of the tube's contents at the end. The clip does not depict the described procedure at all.
level_2: A test tube appears, but no white crystalline sample is visibly placed inside it, or liquid is poured in with no sample ever shown; the rotating motion is missing or looks like vigorous shaking rather than gentle swirling; the final contents of the tube are never actually shown.
level_3: A dry test tube receives a small amount of white crystalline powder, a colorless viscous liquid (matching concentrated sulfuric acid) is then added, and the tube is gently rotated, but the view of the tube's contents afterward is blurry, overexposed, or blocked, so the resulting liquid cannot be clearly seen.
level_4: All of the core steps are shown clearly and in the correct order (dry tube, powder added, roughly 2 mL of liquid acid added, gentle rotation), and the tube's contents are visible afterward as a single uniform liquid with no visible solid remaining; one minor flaw only, such as a glare on the glass or a brief hand occlusion during rotation.
level_5: The full sequence is shown with no ambiguity: an empty dry test tube receives a visible amount of fine white crystalline powder; a clearly measured ~2 mL of colorless liquid is dispensed in (e.g., via a syringe with a readable volume mark); the tube completes a full 360° gentle clockwise rotation over about 5 seconds; afterward the tube holds a single, fully transparent, particle-free liquid with no bubbles, held still and unobstructed in frame long enough to be clearly observed.

Scientific and Causal Correctness rubric:
level_1: The resulting liquid is a color that is chemically implausible for this reaction (e.g., blue, green, purple, or glowing); or vigorous bubbling, smoke, or visible charring occurs; or the powder stays an undissolved white suspension; or there is no visible connection between adding the acid or rotating the tube and any change in the liquid.
level_2: The resulting liquid is colorless or only pale yellow (too light for this reaction), or looks cloudy/turbid (suggesting the powder never fully dissolved); rotation happens but nothing visibly changes; or the order of events is wrong (e.g., the liquid already looks colored before the acid is added).
level_3: The liquid does turn an amber-brown color, but it looks slightly hazy or still has visible specks in it; a little undissolved solid may still be seen after rotation; the overall order (add acid, rotate, color develops, observe) is right, but the color seems to appear oddly early, before rotation has had a chance to mix things.
level_4: A clear amber-brown liquid forms fairly quickly once rotation begins, with no leftover solid, no bubbles, and no visible heat haze or charring; the color only appears after the acid is added and mixed in, making the cause-and-effect clear; one small deviation is acceptable, such as the amber-brown hue looking slightly lighter or darker than a textbook example while still being clearly recognizable as amber-brown.
level_5: The powder dissolves completely and quickly into a clear, uniform amber-brown liquid, matching the color reported for fluconazole reacting with concentrated sulfuric acid; there is no precipitate, no bubbling, and no fuming at any point; the color and clarity stay steady for at least about 3 seconds once rotation stops; the whole cause-and-effect chain (add acid to sample, rotate, amber-brown color develops) reads clearly and unambiguously.

Spatiotemporal Consistency rubric:
level_1: The test tube appears to float with no hand holding it; the hand enters the frame from an inconsistent or physically odd angle; the syringe appears disconnected from the hand holding it; the powder vanishes from the tube and reappears; the rotation direction suddenly reverses; the lighting changes dramatically partway through the clip.
level_2: The hand or test tube looks unanchored: the hand shakes excessively, the tube tilts more than about 30° during rotation, making a spill look imminent, the acid volume has no visible reference (no syringe markings or liquid level shown); there are long unexplained pauses between the key steps (placing the sample, adding acid, rotating, observing).
level_3: The test tube stays close to upright (tilting no more than about 5°) on a stable surface, the hand rotates it with a consistent grip and motion, and the syringe shows a readable ~2 mL mark, but there is one minor flaw, such as a brief moment where the hand blocks the view of the tube right as the acid is added, or a single flicker in the lighting.
level_4: The full sequence flows smoothly: the test tube rests steadily on the bench, the hand enters, places the powder, withdraws, returns with a syringe showing a clear ~2 mL mark, dispenses the acid into the tube, and rotates it at a steady, even pace; there is no blocking of the view, no lighting change, and no visible warping of the tube or hand between steps.
level_5: All of the 4-point criteria are met, and every transition between actions (placing the powder, adding acid, rotating, holding still to observe) flows without a visible cut or jump; the hand and tube keep consistent proportions and lighting throughout; the rotation traces a smooth, steady circular motion with no sudden speed changes; the dissolving of the powder is shown progressing gradually rather than changing instantly from one moment to the next.