Domain: Natural Science — Atmospheric Science
Target concept: Demonstration of Cloud Condensation Nuclei Using Humid Air and Cigarette Smoke in a Transparent Chamber

Video generation prompt: Two transparent chambers containing moist air are placed side by side; cigarette smoke is introduced only into the left chamber, and then both chambers are rapidly cooled simultaneously.

Evaluation guide:
(i) Target concept: Heterogeneous nucleation of water vapor via aerosol particles under supersaturation.
Minimum mechanism: Presence of insoluble hygroscopic particles (smoke) lowers critical supersaturation threshold, enabling rapid phase change upon cooling; absence of such particles delays condensation despite identical thermodynamic conditions.
(ii)Storyline: Frame 0–2: Two clear, identical transparent chambers side-by-side, both containing invisible humid air; Frame 3–4: Cigarette smoke enters left chamber only, forming a visible gray-brown plume suspended centrally; Frame 5–6: Cooling initiation signaled by uniform visual cue (e.g., frost rings appearing on chamber exteriors, or ambient dimming); Frame 7–10: Condensation emerges first and more densely in left chamber (nucleated), while right chamber remains mostly clear or shows sparse, delayed condensation; fixed frontal viewpoint ensures left/right distinction remains unambiguous throughout; all phenomena occur within chamber volumes—no external interference or overlay.

Manual:
Experimental Procedure
1. Place two identical transparent chambers side-by-side, filled with humid air.
2. Introduce cigarette smoke exclusively into the left chamber.
3. Rapidly cool both chambers simultaneously.
Observation of Experimental Phenomena
Left chamber develops dense, widespread condensation (cloud/fog); right chamber develops little or no condensation.
Summary of Experimental Principles
Cigarette smoke provides cloud condensation nuclei (CCN); humid air requires nuclei to condense when cooled. Without CCN (right chamber), supersaturation occurs but condensation is delayed or suppressed.

Prompt Grounding rubric:
level_1: No two transparent chambers appear together in frame; no cigarette smoke is introduced into either chamber; no cooling action is shown; the two chambers are not shown positioned next to one another; nothing suggests the two cooling events happen at the same time.
level_2: Two transparent chambers are present but are not positioned next to each other (e.g., stacked, far apart, or only one in frame at a time); cigarette smoke appears in neither chamber or in both chambers; cooling action is absent or applied to only one chamber; nothing indicates the two cooling actions happen at the same time.
level_3: Two transparent chambers are placed next to each other; cigarette smoke is introduced into exactly one chamber (the left one); a cooling action is visually initiated for both chambers; however, either which chamber is "left" is unclear from the framing, or the smoke introduction and the onset of cooling are not clearly ordered in time (e.g., the smoke appears after cooling has already started).
level_4: Two transparent chambers are placed next to each other with an unambiguous left/right orientation; cigarette smoke is introduced exclusively into the left chamber before cooling begins; a cooling action (e.g., visible condensation onset, frost forming on the chamber exterior, or misting) visibly begins in both chambers at close to the same time; the chambers, smoke plume, and condensation are all fully visible and correctly positioned.
level_5: All elements of 4-score satisfied, and additionally: which chamber is "left" stays unambiguous throughout (e.g., a fixed camera keeps a consistent left-right frame layout); smoke is introduced only once, only into the left chamber, and stops before cooling begins; condensation's onset in the two chambers looks essentially simultaneous to the eye, with no obvious lag or staggering between them, and no extraneous objects, overlays, or occlusions appear in frame.

Scientific and Causal Correctness rubric:
level_1: No condensation observed in either chamber; smoke appears in right chamber or both; condensation appears before smoke or before cooling; condensation appears only in smoke-free chamber.
level_2: Condensation appears in only one chamber, but that chamber is the right (smoke-free) one; or condensation appears identically in both chambers; or smoke is present but no condensation forms in left chamber; or condensation forms without any cooling action shown.
level_3: Condensation appears in both chambers, but the left chamber shows denser, earlier, or more extensive condensation than the right chamber; smoke is present only in left chamber; cooling action is shown; however, the contrast in condensation density/extent is present but not visually unambiguous (e.g., due to lighting, motion blur, or partial occlusion).
level_4: Condensation appears in both chambers; left chamber exhibits clearly greater condensation density and extent than right chamber; smoke is present only in left chamber and remains visibly distinct during cooling; no condensation appears in right chamber before left; causal sequence is intact: smoke → cooling → asymmetric condensation.
level_5: All elements of 4-score satisfied, and additionally: condensation in left chamber is markedly denser and more spatially extensive (e.g., fills >50% of chamber volume vs. <20% in right); smoke remains suspended and unmixed with chamber walls; no condensation appears in right chamber until *after* left chamber condensation is already visible; no anomalous color shifts (e.g., yellow smoke turning white, or blue tint on condensation).

Spatiotemporal Consistency rubric:
level_1: The chambers teleport to different positions between frames; the smoke plume appears or disappears with no visible drift causing it; condensation fogs up a chamber instantly with no gradual fade-in; the pattern of light/reflection on the chamber walls jumps or flips as if the light source moved with no explanation; the outline of a chamber warps or breaks.
level_2: One chamber flickers or vanishes for two or more consecutive frames; the smoke plume starts or stops abruptly with no visible trail showing how it got there; condensation appears fully formed within a single frame rather than building up; the camera angle shifts partway through the clip; a background object changes identity or position between shots.
level_3: Both chambers, the smoke, and the background stay continuously visible throughout; neither chamber teleports nor visibly warps; the smoke drifts smoothly and the condensation's cloudiness builds up gradually rather than snapping into place; however, brief jitter or a momentary out-of-focus frame (no longer than a fraction of a second) may occur.
level_4: All elements of score 3 are present AND both chambers keep fixed positions and proportions relative to each other and the background; the smoke moves with natural, laminar drift with no jerky starts/stops; condensation builds up with a smooth, continuous increase in haziness and coverage; the reflection/glare visible on the chamber walls keeps the same position and brightness in both chambers throughout, with no sudden shift in one chamber but not the other; there are no cuts, zooms, or re-framing.
level_5: All elements of score 4 are present AND there is no visible drift, shake, or misalignment of either chamber or the smoke plume across the whole clip; motion blur is proportionate to speed (the fast-drifting smoke shows an appropriate soft blur, while the slower condensation build-up looks sharp); the two chambers' edges show no shifting relative to the background as the camera holds its framing; no lens distortion is visible at either chamber's corners.