Domain: Engineering — Civil & Environmental Engineering
Target concept: Advanced Oxidation Processes

Video generation prompt: Two beakers containing chemical waste water with high COD are displayed side by side. The left beaker is dosed with Fenton's reagent (ferrous sulfate + hydrogen peroxide), while the right beaker is dosed with an equal volume of distilled water. Both are stirred until complete reaction occurs.

Evaluation guide:
(i) Target concept: Visual demonstration of differential oxidative degradation efficacy between Fenton"s reagent and inert control in wastewater.
Minimum mechanism: Hydroxyl radical generation requires both Fe²⁺ and H₂O₂; absence of either component prevents •OH formation; COD reduction correlates with observable decolorization and clarification in real-time under standard lab lighting.
(ii)Storyline: Frame opens on static wide shot of two identical beakers containing identically turbid, amber-colored wastewater → left beaker receives Fenton reagent (visually distinct dual-source or labeled addition) → right beaker receives distilled water (labeled or clearly non-reactive source) → simultaneous stirring begins for both → left beaker undergoes continuous, monotonic lightening and clarity gain while right remains unchanged → stirring ceases → final state held for ≥1 second with stable side-by-side comparison; entire sequence viewed from fixed frontal perspective with neutral background and consistent illumination.

Manual:
Experimental Procedure
1. Place two identical transparent glass beakers side-by-side.
2. Add equal volumes of high-COD wastewater to both beakers.
3. Dose left beaker with Fenton"s reagent (ferrous sulfate + hydrogen peroxide).
4. Dose right beaker with equal volume of distilled water.
5. Stir both beakers simultaneously until reaction completes.
Observation of Experimental Phenomena
Left beaker: progressive lightening of color and increase in transparency; right beaker: no change in color or transparency.
Summary of Experimental Principles
Fenton"s reagent generates hydroxyl radicals (•OH) that oxidize organic pollutants, reducing COD and decolorizing wastewater; distilled water causes no chemical change.

Prompt Grounding rubric:
level_1: Only one beaker is visible, or the two beakers are not placed next to each other, or neither beaker ever receives a visible liquid addition, or stirring never appears in either beaker.
level_2: Two beakers sit side by side, but at least one of these is missing: a distinct liquid addition into the left beaker that could represent Fenton's reagent, a distinct liquid addition into the right beaker that could represent distilled water, or stirring shown in both beakers.
level_3: Two beakers sit side by side; the left beaker receives a clearly separate liquid or reagent addition consistent with Fenton dosing (e.g., a rust-tinted ferrous sulfate solution and a peroxide addition, or one labeled combined dose); the right beaker receives a plain liquid addition consistent with distilled water; both beakers are stirred; the two beakers hold visibly equal starting volumes of wastewater on the same surface.
level_4: Everything described for the previous level holds, and in addition: both dosing steps clearly finish before stirring begins in each beaker; the two beakers match each other in shape, size, and glass appearance; and any on-screen labels are legible and sit next to their own beaker rather than floating elsewhere.
level_5: Everything described for the previous level holds, and in addition: the liquid added to each beaker looks like the same height/amount; the stirring tool used (rod, spoon, or stirrer) is the same type and moves in a similar manner in both beakers; and no unrelated object (gloves, spare containers, a timer, a phone) enters the frame at any point.

Scientific and Causal Correctness rubric:
level_1: Neither beaker shows any color change; or both beakers change color the same way; or the right (distilled-water) beaker becomes lighter/clearer while the left (Fenton-dosed) beaker does not; or any lightening begins before the dosing step happens.
level_2: The left beaker changes color, but in the wrong direction: it turns darker or more turbid rather than lighter and clearer; or the right beaker also visibly lightens or clarifies; or the left beaker's color shift happens as a sudden jump rather than a gradual fade; or the left beaker's hue changes without any matching gain in transparency.
level_3: The left (Fenton-dosed) beaker progressively lightens from its starting turbid amber/brown appearance and becomes visibly more transparent as stirring continues; the right (distilled-water) beaker shows no change in hue or turbidity from its own starting appearance; the left beaker's lightening does not reverse partway through; both beakers hold their final appearance once stirring stops.
level_4: Everything described for the previous level holds, and in addition: the left beaker's end-of-video color and clarity are clearly lighter than its own opening frame; the right beaker's end-of-video appearance matches its opening frame in hue and turbidity; and if any fine bubbling or a pale rust-colored floc appears in the left beaker, it is treated as consistent with genuine Fenton chemistry (iron-catalyzed peroxide decomposition and iron hydroxide formation) rather than scored as an error; what matters here is the net lightening/clarifying trend, not the total absence of bubbles or floc.
level_5: Everything described for the previous level holds, and in addition: the color reduction in the left beaker spreads evenly through the whole liquid rather than staying confined to the top layer or one side; the right beaker's hue and turbidity stay visibly identical to its own opening frame for the entire video; and the contrast between the two beakers' final appearance is obvious enough that a viewer comparing them side by side would need no explanation.

Spatiotemporal Consistency rubric:
level_1: Either beaker vanishes and reappears, or instantly relocates to a different spot on the bench between frames; the stirring motion cuts out and restarts without any transition; the camera view suddenly pans, tilts, or zooms partway through; or the room's lighting suddenly flashes, flickers, or goes dark partway through the sequence.
level_2: Both beakers stay in place, but the glass appears to warp, bend, or bounce light in ways inconsistent with rigid glassware; the stirring motion skips ahead in visible jumps rather than moving continuously; the shadows the beakers cast swing to a new direction or disappear partway through; or background elements flicker or tear.
level_3: The two beakers stay in the same side-by-side spots relative to each other and the bench for the whole video; stirring is smooth and continuous in both; the room's light source keeps the same direction, brightness, and softness from the first frame to the last; neither beaker's glass warps, clips through the other beaker, or overlaps unnaturally with it.
level_4: Everything described for the previous level holds, and in addition: each beaker's rim and liquid surface keep a believable, unchanging curve and sharp edge throughout; the stirring rod or tool stays under the liquid surface in both beakers rather than popping above it; there is no sideways drift between the two beakers that would suggest the camera itself moved; and the background stays plain and undistracting the whole time.
level_5: Everything described for the previous level holds, and in addition: the liquid surface in each beaker keeps a physically believable meniscus shape without turning unnaturally flat or overly domed; stirring produces a believable, evenly shaped swirl in both beakers; the color you see in each beaker is not thrown off by any color fringing or sudden shift in the scene's lighting; and neither beaker blurs into visible ghost trails or falls out of focus relative to the other at any point.