Domain: Natural Science — Chemistry
Target concept: Liquid mixture solidifies into a rigid transparent solid

Video generation prompt: Mix 0.5 g of liquid epoxy resin with 0.5 g of liquid curing agent, and react at 80°C for 10 minutes. Observe the color and morphology of the product using time-lapse photography.

Evaluation guide:
(i) Target concept: Thermosetting polymerization of epoxy-curing agent system under thermal acceleration.
Minimum mechanism: Mixing enables molecular contact between resin epoxide groups and curing agent amine/hydroxyl groups; thermal energy overcomes activation barrier, enabling irreversible covalent cross-linking that restricts chain mobility → macroscopic solidification and transparency retention.
(ii)Storyline: [Frame 0] Two identical containers each hold a clear pale yellow liquid (epoxy resin, curing agent), side-by-side, static, fixed viewpoint. → [Frame 1] Liquids poured simultaneously into third container; stirring begins immediately. → [Frame 2] Homogeneous liquid fills container, meniscus stable, no separation. → [Frame 3] Container placed onto heated surface (visible thermal glow or label); liquid surface remains fluid but meniscus subtly flattens. → [Frame 4] Progressive stiffening: surface ripples dampen, meniscus arrests, edge definition sharpens. → [Frame 5] Fully rigid transparent solid occupies container with geometric precision; background fully legible through it; no motion, no deformation. All transitions must be continuous, causally linked, and visible within fixed frame.

Manual:
Experimental Procedure
1. Place 0.5 g liquid epoxy resin in container A and 0.5 g liquid curing agent in container B.
2. Simultaneously pour both liquids into container C and stir until homogeneous.
3. Place container C on 80°C heating surface for 10 minutes.
Observation of Experimental Phenomena
• Two clear, pale yellow liquids before mixing.
• Homogeneous pale yellow liquid after mixing.
• Gradual loss of fluidity during heating.
• Final product is rigid, transparent, and amber-tinted.
Summary of Experimental Principles
Epoxy resin and curing agent undergo exothermic addition polymerization upon mixing; elevated temperature accelerates cross-linking, converting liquid mixture into a rigid, transparent thermoset network via covalent bond formation.

Prompt Grounding rubric:
level_1: No visible epoxy resin or curing agent containers; no mixing action shown; no heating apparatus present; no time-lapse visual progression; none of the required materials (liquid epoxy resin, liquid curing agent, container, heat source) appear.
level_2: At least one correct material appears (e.g., two identical clear liquids in separate containers), but no mixing occurs; or mixing occurs without two distinct liquid inputs; or heating is implied without a visible 80°C thermal context (e.g., no hotplate, oven, or thermal indicator); sequence is disordered or missing ≥2 required steps.
level_3: Two separate liquid substances are visibly present before mixing; mixing action (e.g., pouring or stirring) is shown between them; a heating context (e.g., hotplate, oven chamber, or labeled 80°C environment) is present; final solid product appears, but at least one of: container identity is ambiguous, mixing ratio cannot be confirmed as equal, or time-lapse progression lacks clear pre-/post-reaction contrast.
level_4: Two distinct liquid substances (same volume appearance, same container type, side-by-side placement) are shown before mixing; mixing action is unambiguous and fully contained within one vessel; heating context is visually anchored (e.g., sample on hotplate with visible thermal glow or labeled setting); final state shows rigid, transparent solid; all core objects and actions from posted_prompt are present and correctly ordered; only non-core flaws exist (e.g., minor lighting flicker, brief occlusion, container label unreadable).
level_5: Two identical small containers each hold a clear liquid; liquids are poured/stirred into a third container with no spillage or ambiguity; container remains stationary on a clearly identifiable 80°C heating surface throughout; time-lapse progression shows continuous transition from two separate liquids → homogeneous mixture → rigid transparent solid; all objects (epoxy resin, curing agent, mixing container, heat source) are uniquely identifiable by form, placement, and role; no occlusion, no duplication, no substitution, no temporal jump.

Scientific and Causal Correctness rubric:
level_1: Final product is liquid, opaque, colored, or powder-like; no state change occurs; or solid appears before mixing/heating; color shifts contradict chemistry (e.g., yellow resin turns blue); no causal link between mixing + heating and solidification is visually supported.
level_2: Final state is solid but not transparent; or solid is transparent but not rigid (e.g., wobbles, deforms under gravity); or color changes inconsistently (e.g., deep amber → white); or solid forms without prior mixing or without heating context; or mixing occurs but no observable transformation follows.
level_3: Final product is rigid and transparent, matching expected epoxy thermoset morphology; color is consistent with typical uncured/cured epoxy (e.g., pale yellow to amber, no drastic hue shift); mixing and heating both occur before solidification; but either: transparency is partially obscured (e.g., surface haze, bubbles), rigidity is not verifiable (no static hold or edge definition), or color change is absent despite known curing browning.
level_4: Final product is rigid (maintains sharp edges, no sagging or flow under gravity), fully transparent (background text/lines fully legible through it), and exhibits expected amber-to-amber+slight-darkening color progression; mixing precedes heating, heating precedes solidification; no contradictory phenomena (e.g., bubbling without heat, cracking during cure, premature hardening); only non-core scientific flaws exist (e.g., minor bubble inclusion, uniformity of gloss).
level_5: Rigid transparent solid occupies full container volume with geometrically defined edges; zero distortion of background objects viewed through it; color is uniformly pale amber pre-mix → slightly darker amber post-cure, with no discoloration zones, streaks, or cloudiness; mixing produces homogeneous liquid phase; heating initiates gradual loss of fluidity; solidification completes with abrupt cessation of surface meniscus movement; all phenomena align precisely with epoxy-curing kinetics and optical properties; zero deviation from subject knowledge.

Spatiotemporal Consistency rubric:
level_1: Objects teleport (e.g., liquids appear inside container without pouring); container vanishes/reappears; lighting changes abruptly mid-sequence; solid forms in frame without prior presence of mixture; camera angle jumps >90° between shots; structural integrity breaks (e.g., container cracks then reforms).
level_2: At least one major spatiotemporal rupture: e.g., mixing action starts with full container already filled; heating element appears only after solid forms; time-lapse shows discontinuous frames (jumps, freezes, duplicates); container rotates or translates significantly without mechanical cause; shadow direction flips without light source movement.
level_3: All objects remain continuously present and spatially coherent: containers maintain fixed relative positions; mixing vessel stays centered; heating surface remains in view; time-lapse shows monotonic progression (no reversal, no skipping stages); lighting and shadows remain consistent in direction and intensity; but minor issues exist: e.g., one frame blur, brief reflection artifact, or slight parallax shift in background.
level_4: Zero object teleportation, zero lighting discontinuity, zero frame duplication/jump, zero container repositioning; all motion is physically plausible (e.g., stirring has inertia, liquid sloshes naturally); perspective remains strictly fixed (no zoom, pan, tilt); background elements retain stable alignment; only non-core SC flaws: e.g., single-frame motion blur on stirrer, negligible lens flare.
level_5: Perfect spatiotemporal continuity: container position, orientation, and scale invariant across all frames; no parallax shift in any background reference; stirring motion is smooth and biomechanically consistent; heating surface glow increases gradually and uniformly; liquid surface tension evolves continuously; solidification manifests as progressive meniscus arrest without flicker or stutter; every inter-frame transition is physically natural and optically seamless.