Domain: Healthcare — Pharmaceutical Chemistry
Target concept: Structural Degradation and Color Change of Drugs at High Temperatures

Video generation prompt: Take a small amount of vitamin B6 powder, place it in a porcelain evaporating dish, and heat it in an oven at 100°C for 8 hours. After removal, examine the powder's appearance, then add 5 mL of distilled water to dissolve it.

Evaluation guide:
(i) Target concept: Extended dry-heat exposure of solid vitamin B6 powder can produce a visually detectable shift toward pale yellow, without changing the powder's ability to dissolve readily in water.
Minimum mechanism: Vitamin B6 must be heated in solid state at ~100°C for a duration long enough (a multi-hour dry-heat exposure, consistent with standard pharmaceutical forced-degradation/stress-testing protocols) to let a small fraction of the material slowly oxidize, producing trace chromophoric byproducts that tint the bulk powder, while staying below the charring threshold (~150°C) and well below pyridoxine's melting point (~205-212°C); the parent compound itself remains freely water-soluble throughout, so its dissolution behavior is not expected to change.
(ii) Storyline: [Frame 0-2] White vitamin B6 powder placed in porcelain evaporating dish on bench. [Frame 3-4] Dish inserted into oven cavity; oven display shows 100°C with an elapsed-time readout advancing toward 8 hours (shown compressed on screen). [Frame 5-6] Dish removed; powder now pale yellow (uniform, no browning). [Frame 7-8] Distilled water poured into dish; powder begins immediate dispersion. [Frame 9-10] Fully dissolved, clear solution with no residue. All events occur from a fixed frontal lab-bench viewpoint; the oven interior is occluded (no powder visible during heating); appearance is assessed only after removal; dissolution is confirmed by the absence of particles and by optical clarity.

Manual:
Experimental Procedure
1. Place a small amount of white vitamin B6 powder into a porcelain evaporating dish.
2. Heat the dish in an oven at 100°C for 8 hours.
3. Remove the dish and examine the powder's appearance.
4. Add 5 mL of distilled water to the dish.
Observation of Experimental Phenomena
After the extended heating period, the powder shifts from white to a uniform pale yellow; when water is added it dissolves completely, forming a clear solution with no visible residue.
Summary of Experimental Principles
Pyridoxine (vitamin B6) is comparatively heat-stable (melting point ~205-212°C) and is already freely soluble in water at room temperature. Prolonged solid-state exposure to moderate heat -- as used in standard pharmaceutical dry-heat forced-degradation/stress testing, typically run for several hours at ~100-110°C -- causes slow oxidative degradation of a small fraction of the material, generating chromophoric byproducts that tint the bulk powder pale yellow, without producing charring (~150°C threshold) or melting. Because the parent pyridoxine molecule in the remaining bulk is unaffected and stays freely water-soluble, the discolored powder still dissolves readily in water; the color change reflects surface-level oxidative degradation, not a change in solubility.

Prompt Grounding rubric:
level_1: None of the four required elements is shown: no vitamin B6 powder, no porcelain evaporating dish, no oven, and no distilled water container; neither the placement-in-dish, oven-heating, post-removal examination, nor water-addition action occurs anywhere in the video.
level_2: Only one of the four required elements is clearly shown (the powder, or the dish, or the oven, or the water), or a wrong substitute appears in its place (e.g., a glass beaker instead of the porcelain evaporating dish, or a jug of tap water instead of distilled water); at least one core action from the sequence -- place powder, heat in oven, remove and examine, add water -- is missing entirely, or water is added before the oven step.
level_3: All four elements are present -- a fine white powder, a shallow ceramic evaporating dish, an oven with a visible temperature readout, and a clear liquid identified as distilled water -- and the four actions (place, heat, remove/examine, add water) occur in the correct order; however at least one setup detail is off, such as the dish not reading clearly as porcelain-style ceramic, the oven's temperature display being unreadable, the water volume clearly not close to 5 mL, or the powder amount clearly more than a 'small amount' (e.g., filling the dish).
level_4: All four elements are unambiguous: the powder is a fine white solid; the dish is a shallow, matte, light ceramic evaporating dish (not a flat plate or glass beaker); the oven is a fully enclosed heating unit with a legible ~100°C readout; the water is a visibly clear liquid poured from a container identifiable as distilled water. The four-step sequence (place, heat, remove/examine, add water) runs with no step skipped, added, or reordered, and no object is substituted for an incorrect type.
level_5: Everything required for score 4 holds, and in addition every element carries a convincing finishing detail: the ceramic dish shows a visible glaze sheen and shows no cracking, warping, or condensation right after coming out of the oven; the oven readout stays steady at ~100°C with its heating indicator lit while the dish is inside; the water is poured in a continuous stream with a visible meniscus as it fills the dish. The whole sequence plays as one continuous take (or a cut that preserves camera position and lighting), with no object duplicating, vanishing, or swapping type between the heating and post-heating shots.

Scientific and Causal Correctness rubric:
level_1: The powder's appearance after heating is scientifically inconsistent with the described process: it stays pure white after the full 8-hour bake, or instead turns black/brown/charred, or the video shows no dissolution at all when water is added -- any of these misrepresents the mild oxidative discoloration vitamin B6 undergoes under prolonged moderate heat.
level_2: The powder does show some discoloration after heating, but water added to it afterward leaves visible undissolved grains or cloudiness -- implying the heat treatment reduced its ability to dissolve -- OR the reverse pairing occurs (dissolution looks complete but the powder never changed color at all), breaking the intended pairing of 'mild surface oxidation' with 'still freely water-soluble'.
level_3: The powder turns a yellow-tinted shade after heating and fully disperses when water is added, but with a flaw: the color change looks patchy or streaked rather than roughly even across the dish, or a few grains are still visibly floating or settled a couple of seconds after the water is poured, or the color is already visible through the oven's window/door during heating rather than only being revealed once the dish is removed.
level_4: The powder is clearly uniform white before heating, comes out an even pale-yellow tint (not brown, orange, or grey) after the 8-hour bake, and dissolves completely on contact with the 5 mL of water within the shown clip (no floating grains, no lingering cloudiness); the order -- heat, then examine color, then add water, then dissolve -- is never broken or shown out of sequence.
level_5: Everything in score 4 holds, and additionally: the pale-yellow tint reads as a soft, warm, desaturated straw color (clearly distinguishable from white but nowhere near brown, orange, or grey -- think weak chamomile tea, not caramel), the powder is never visible while the oven door is shut (so no premature color reveal is possible), and once water contacts the powder it disperses and clears within a couple of seconds with no swirling or stirring needed -- visually confirming that surface-level oxidation changed only the powder's color, not its ability to dissolve.

Spatiotemporal Consistency rubric:
level_1: The evaporating dish or the powder inside it jumps between clearly different spots on the bench with no motion shown; the oven door swings open with nothing/no one moving it; water fills the dish instantly with no pour ever shown; or the room's brightness swings from bright to dark (or back) partway through the clip with no visible light source causing it.
level_2: Two or more clear breaks in continuity occur: the amount of powder visibly changes between shots even though nothing was added or removed; the dish faces one way going into the oven and a different way coming out with no turn shown in between; or the oven's displayed heating progress doesn't match what's on screen (e.g., the readout still shows the very start of the cycle while the powder is already fully yellow).
level_3: One notable continuity slip occurs -- for example, the dish is seen inside the oven with the powder visible, then cuts to sitting on the bench with matching light but no removal motion shown in between; or water is poured into the dish but the liquid level never visibly rises; or the powder's color changes across a cut without the dish's position or angle carrying over -- but apart from that single slip, objects stay put within each individual shot and the room lighting doesn't swing around.
level_4: No such slip occurs: the dish travels in one continuous, physically sensible path from oven to benchtop; the powder stays put inside the dish the whole time; the shadow cast by the dish keeps pointing the same way and the same strength across the clip; the poured water visibly speeds up and slows down naturally and the dish's liquid level rises as it's poured; nothing in the shot stretches, spins in place, or changes size on its own; the oven-door-opening, dish-lifting, and pouring motions all look physically natural.
level_5: Everything in score 4 holds, and additionally the motion reads as fully continuous start to finish: no frame repeats or jumps backward, no stutter in the dish's or water's movement; the camera's framing of the dish stays at the same distance and angle throughout so its size and perspective never subtly shift; the room lighting never flickers or pulses; the dish is lifted straight up and out of the oven rather than sliding sideways through it, and the poured water follows a natural, gravity-curved stream into the dish.