Each act follows predict → observe → explain → compare → apply: s0 only records your prediction (no answer yet); s1–s4 ask their question after the animation, and a correct answer unlocks the next act; s5 has two questions in turn. The stage, captions and progress bar share one paused timeline, so nothing animates on its own; leaving the page or switching tabs pauses it.

Source of the numbers (W4 materials, calculation check): pKa = 4.757; equivalence point 18.75 mL, pH 8.695; phenolphthalein pH 8.2 falls at 18.744 mL, 0.006 mL from the equivalence point (less than one drop); the dpH/dV peak from 0.25 mL differences is at 18.62 mL. The red-wine curve is a multi-organic-acid model drawn for shape only, not a measurement, and the stage shows no scale for it.

This version uses synchronized text captions and has no narration; the pre-lab video and this page share the same storyboard and drawing components.

W4 Manual vs Automatic Titration lab materials · Ch22 Acidity (Nielsen) slides · Storyboard and QA design reference (FW1201/code-animation-explainer)