Domain: Natural Science — Physics
Target concept: The dissolution of calcium chloride in water results in a significant increase in solution temperature, releasing heat.

Video generation prompt: Add calcium chloride through the resealable cap of a container of water that has a thermometer sealed into its lid, then close the cap and observe the change in the thermometer reading as the solid dissolves.

Evaluation guide:
(i) Target concept: Exothermic dissolution of calcium chloride in aqueous solution.
Minimum mechanism: Solid CaCl₂ must directly contact bulk liquid water inside a container that stays closed except for the brief moment the solid is introduced through its resealable cap; heat release must manifest as a measurable rise in the thermometer reading, with no competing endothermic or kinetic artifacts (e.g., evaporation, mixing work, incomplete wetting).
(ii)Storyline: [Frame 0–2] Container with water filling roughly the lower two-thirds, thermometer already sealed into the lid with its bulb submerged, resealable cap on the lid closed. [Frame 3–4] The cap is opened, white crystalline calcium chloride enters through the opening and contacts the water surface, then the cap is closed again. [Frame 5–7] The solid particles sink, spread out, and shrink in number while the thermometer reading climbs. [Frame 8–10] The solid has fully dissolved; the reading holds at a higher value; the water stays clear and undisturbed. Perspective: fixed frontal view, the whole container in frame, the thermometer bulb and water surface never obstructed; one continuous shot with no cuts or repositioning.

Manual:
Experimental Procedure
1. Seal a thermometer through the lid of a container of water so its bulb stays submerged, leaving a separate small resealable cap on the lid closed.
2. Open the cap, add white crystalline calcium chloride into the water, and close the cap again.
3. Observe the thermometer reading immediately after contact and during dissolution.
Observation of Experimental Phenomena
The thermometer reading rises continuously and steadily while the white solid dissolves completely in the water; the liquid stays colorless and transparent; no gas, precipitate, or color change occurs.
Summary of Experimental Principles
Calcium chloride dissolution in water is an exothermic process: energy is released as heat, causing a measurable rise in temperature.

Prompt Grounding rubric:
level_1: No container is visible; no thermometer is present; no calcium chloride solid is shown; no water is shown; no action of adding or dissolving is depicted.
level_2: At least one of the container, thermometer, white crystalline solid, or water appears, but they are never shown together in one coherent scene, or the solid appears without ever being added into the container (e.g., it is already dissolved in the first frame, or the thermometer appears only after dissolution is already complete).
level_3: The container, thermometer, white crystalline calcium chloride, and water are all present in the same scene; a cap or port on the container is opened, the solid is introduced into the water through it, and the cap is closed again; the thermometer bulb stays visible inside the container throughout; the solid enters the water before any change in the thermometer reading is shown.
level_4: Everything described at the 3-point level holds, and in addition: the thermometer bulb stays submerged in the water the whole time; the solid visibly touches the water surface the moment it enters; the container stays closed except for the brief moment the cap is opened to add the solid; no extraneous object (a hand, a spoon, an extra bottle) lingers in frame once dissolution begins.
level_5: Everything described at the 4-point level holds, and in addition: the solid is added only once, with the cap never reopened afterward; the thermometer is never removed, tilted, or repositioned once it is inserted; the water surface only moves as the solid settles, with no sloshing, splashing, or liquid being topped up; the container wall, thermometer stem, and liquid surface show no visible tearing, doubling, or warping.

Scientific and Causal Correctness rubric:
level_1: The thermometer reading decreases or stays unchanged as the solid dissolves; the water shows a color change, gas bubbles, or a precipitate forming; the solid floats without dissolving, or vanishes with no visible contact with the water; there is no visible causal link between adding the solid and any reading change.
level_2: The thermometer reading rises, but the bulb is not submerged in the water, or the rise begins before the solid touches the water, or the solid dissolves while the thermometer sits outside the liquid, or the apparent temperature rise lines up with some external cause (a hand warming the container, a shift in room lighting) rather than the dissolution itself.
level_3: The thermometer reading rises after the solid contacts the water and while the solid is visibly dissolving; the water stays colorless and clear throughout; the solid shrinks gradually rather than disappearing all at once; no bubbling or steaming occurs; the reading trends upward for as long as undissolved solid remains.
level_4: Everything described at the 3-point level holds, and in addition: the reading only starts climbing once solid-water contact begins; it keeps climbing only while visible solid particles remain; it levels off once the last visible particle has dissolved; no secondary effect (fogging on the container wall, splashing, needle vibration) appears alongside it.
level_5: Everything described at the 4-point level holds, and in addition: the overall rise in the reading is smooth and one-directional — once it starts climbing it does not fall back down before leveling off; the temperature rise tracks the shrinking of the solid within the same short window rather than lagging far behind it; the water shows no visible convection currents or swirling; the container's outer wall shows no shimmer or warping suggesting heat effects beyond a mild, gradual warming.

Spatiotemporal Consistency rubric:
level_1: The container, thermometer, or solid abruptly appears, disappears, or jumps to a new position between frames with no visible cause; the water level changes with no pouring or settling shown to explain it (e.g., jumping from two-thirds full to completely full); the container wall or the thermometer glass looks broken, doubled, or torn; the camera cuts or jumps to a different angle mid-shot; or the lighting or shadows shift abruptly between frames with nothing in the setup to explain it.
level_2: The thermometer appears to pass through the container wall or lid rather than staying seated in its port; the water surface height changes with no solid entering or settling to explain it; the container appears to rotate or slide across the surface with no hand or support shown moving it; the background shifts independently of the container as though the camera itself were unsteady.
level_3: The container stays in the same place and orientation on the surface throughout; the thermometer stays vertically seated in the lid at the same depth; the water surface stays level and horizontal except for the momentary disturbance of the solid entering; the descending solid particles sink at a steady, continuous rate rather than freezing mid-fall or jumping to a new position.
level_4: Everything described at the 3-point level holds, and in addition: the resealable cap opens and closes without misaligning or floating apart from the lid; the thermometer stem stays straight and doesn't bend or flex as solid disperses around it; the water's meniscus keeps a consistent curve against the container wall and the thermometer; the settling solid particles fall along a smooth, gravity-consistent path with no sudden changes in direction.
level_5: Everything described at the 4-point level holds, and in addition: the thermometer bulb stays visibly submerged beneath the water surface in every frame, and the stem never slides loose in the lid; the container's transparent walls show no stretching, shearing, or doubled outlines of the thermometer or the solid particles; the descending particles and the thermometer show no ghosting or strobing as the reading changes; the moment the solid first touches the water and the moment the reading begins to change are both clearly visible, not hidden by motion blur.