What the simulation does – Displacement reaction
A more reactive metal displaces a less reactive metal from a solution of its salt. The four metals are ordered by reactivity: magnesium, zinc, iron, copper (most to least reactive). A metal only displaces another that sits below it in the series.
Layout
The screen has a header, two tabs (Interactive lab and Displacement grid), the 3D scene, and a control strip along the bottom. An Accessibility button opens the full Adapt menu.
Interactive lab (Act one)
Four metal samples stand on a wooden lab bench, each on its own labelled plinth: a magnesium strip, a zinc lump, an iron nail, and a copper strip. At the centre sits a glass beaker on a heat mat, filled with a coloured salt solution (copper sulfate blue by default). A card behind the beaker names the solution.
The flow: you pick a metal, get asked to predict whether it will displace (yes/no), then drag it into the solution and watch. The beaker acts as a generous “funnel” so the sample only has to get roughly near the mouth before it drops in.
When displacement happens (e.g. iron into copper sulfate): a coat of the displaced metal builds up on the sample, loose particles drift to the bottom, the solution colour fades from the old salt’s colour toward the new one (blue → pale green), and the metal surface darkens as it gets coated.
When it doesn’t (e.g. copper into magnesium sulfate, or a metal in its own salt): nothing changes.
Manual reveal: after the reaction settles, the result card does not pop up automatically. A pulsing “Show” pointer appears over the beaker and a “Show the result” button appears in the strip, so pupils can study the beaker as long as they like before revealing the word, symbol, and ionic equations plus a plain-language explanation.
You can also change the salt solution using the Mg/Zn/Fe/Cu buttons in the strip, to try any metal against any salt.
Reactivity ladder
A key down the left highlights the two metals in the current test: blue for the metal being added, amber for the metal locked in the salt, so pupils can read off why displacement will or won’t happen.
Displacement grid (Act two)
A reference matrix: each metal (rows) added to each salt solution (columns), every cell marked with a tick or cross. All the green “yes” cells sit above the diagonal, making the underlying rule visible at a glance. There’s also a five-question challenge that reads straight off the series.
Controls and accessibility
Drag to orbit, scroll or pinch to zoom, tap to select. The Adapt menu carries the full ClassAdapt suite: light/high-contrast default with a dark navy toggle, Irlen colour overlays, protanopia/deuteranopia filters, reading ruler, dyslexia spacing, text scaling, projector mode, object outlines, a buttons-only mode (nothing needs dragging), predict-first toggle, reduce/slow motion, and aria-live announcements throughout.