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Lab experiments · Reactions & qualitative tests: 17 3D models
Every element as an atom, orbitals and bonding, crystals, ions and complexes, real compounds from every field of chemistry, substances in their natural form, electrochemistry and lab experiments (real sizes atoms → lab bench). Each one is a ready-made 3D model you can turn, recolour and place in a figure — open BioDioRama and type its name in the Library search.
- Precipitate colours (test-tube rack) — Eight test tubes of precipitates that identify ions: AgCl white, AgBr cream, AgI yellow, Cu(OH)₂ blue, Fe(OH)₂ green, Fe(OH)₃ red-brown, PbI₂ yellow, BaSO₄ white.
- Transition-metal ion colours (test-tube rack) — Solutions of transition-metal ions and oxoanions in a rack: copper blue, iron(II) green, iron(III) yellow-brown, nickel green, cobalt pink, chromium green-violet, permanganate purple, dichromate orange.
- Silver mirror test (Tollens’) — Warm an aldehyde with Tollens’ reagent in a water bath and the inside of the tube is coated with shining silver.
- Benedict’s test for reducing sugars — Benedict’s reagent heated with sugars in a water bath: blue (none) → green → yellow → orange → brick red (lots of reducing sugar).
- Spotting tile tests (iodine, biuret, indicators) — A white spotting tile with drops: iodine turning blue-black with starch, biuret purple with protein, and indicators in acid and alkali.
- Bromine water test for alkenes — Orange bromine water shaken with an alkene turns colourless (addition across C=C); with an alkane it stays orange.
- Displacement: zinc in copper sulfate — A strip of zinc in blue copper sulfate becomes coated with brown copper as the solution fades — the more reactive metal displaces the less reactive one.
- Silver tree (copper in silver nitrate) — A coil of copper wire in silver nitrate grows glittering silver crystals while the solution turns blue.
- Sodium reacting with water — A pea of sodium whizzes across water in a trough, fizzing and melting into a ball; phenolphthalein turns pink as sodium hydroxide forms.
- Burning magnesium ribbon — Magnesium held in tongs burns with a dazzling white flame, leaving white magnesium oxide (do not look directly at it).
- Thermite reaction — Aluminium powder reduces iron(III) oxide so violently that molten iron pours out of the crucible in a shower of sparks (a demonstration, behind a screen).
- Chemical garden (silicate garden) — Crystals of metal salts dropped into sodium silicate solution grow coloured, plant-like tubes as membranes of metal silicate form and burst.
- Golden rain (lead iodide crystals) — Hot lead iodide solution cools and glittering golden crystals of PbI₂ drift down like rain.
- Rusting experiment (which conditions make iron rust?) — Three nails: in air and water (rusts), in boiled water under oil (no oxygen — no rust), and in dry air over calcium chloride (no water — no rust).
- Cracking liquid paraffin — Paraffin on mineral wool is vaporised over hot porcelain chips; it cracks into smaller alkanes and alkenes, collected over water.
- Making soap (saponification) — Vegetable oil heated with sodium hydroxide solution is hydrolysed into glycerol and soap, which is salted out and pressed into bars.
- Heating hydrated copper sulfate (blue → white) — Heating blue copper(II) sulfate crystals drives off the water of crystallisation; white anhydrous salt is left and water condenses at the cool end.