01 / 05CHEMISTRY · THE ATOM
An electron is a cloud of chances.
Every dot is one draw from the hydrogen 3d wavefunction. Where the dots crowd, the electron is likely to be. The two colors are the two signs of the wave.
Open the orbital lab
SCIENCE LABS IN YOUR BROWSER
From the atom to the orbit, everything is an experiment.
Physics, chemistry and biology. Every experiment is a live model. Change one condition and see what happens.
Explore the labs32 labs193 experimentsFree, no sign up
02 / 05CHEMISTRY · THE CRYSTAL
A grain of salt is one pattern, repeated.
Sodium and chloride ions take turns along every edge, 0.282 nanometres apart. Repeat that pattern a few quintillion times and you have the grain on your table.
Watch a crystal grow03 / 05BIOLOGY · THE CELL
A cell is a city at work.
The nucleus keeps the plans, mitochondria supply the power, membranes build and ship. Ten chapters let you turn it, slice it and zoom in.
Open the cell atlas04 / 05PHYSICS · WAVES
Two ripples add up to a pattern.
Where crest meets crest the water rises. Where crest meets trough it lies still. This surface is that sum, computed as you watch. Light and sound obey it too.
Open the waves lab05 / 05PHYSICS · ORBITS
An orbit is a fall that never lands.
Each dot solves Kepler's equation on your graphics card, frame by frame. Fast near the planet, slow far away, which is why the dots bunch up at the far end.
Launch a satelliteYou understand a thing when you can change it. So every lab here hands you the controls.
THREE SUBJECTS
Pick the question you are curious about.
Physics
From a toy train to a satellite, from circuits to the double slit.
16 labs83 experiments
Enter
Chemistry
From electron clouds to crystals, from colliding molecules to the titration bench.
14 labs95 experiments
Enter
Biology
Slice open a cell, then test an enzyme, count a flask of yeast and draw a segregation ratio.
2 labs15 experiments
Enter
TRY ONE HERE
Stop reading. Drag a slider.
Light passes two slits and lands on a screen one metre away as bright and dark bands. Change the color or move the slits apart and the bands are recomputed at once.
HOW EVERY LAB IS BUILT
The model comes first. The picture follows.
Start from a question
After the brakes, what keeps moving? Each experiment opens with an everyday question, not a formula.
Change one condition
Drag the weight, swap the gas, raise the voltage. Every reading on screen is computed by the model on the spot. Nothing is a recording.
Let the data answer
Readouts, charts and the scene move together. Each model has to pass its own numeric checks before a release.
THE FULL INDEX
Every experiment, on one page.
Click any name to open that experiment.
Physics83
- Mechanical motionIs it moving?Is the passenger moving or still?How far has the train travelled?Does it keep the same speed?What is the average speed for the whole trip?
- Inertia
- Motion and Force LabTicker tapeNewton tubeTilting boardPhotogatesElevator
- Curved Motion and Energy LabProjectile launcherCentripetal force turntableSatellite orbitsIncline and winchRoller coaster
- Simple Machines LabLeverPulleysRampWindlassPulley block
- Mass, Density and Pressure LabElectronic balanceDisplacement in a cylinderLittle table on a spongeMetal cylinders
- Pressure and Buoyancy LabPressure gaugeShip lockWeighing methodOverflow canSubmarineShip
- Heat and Changes of State LabTest tube in a water bathBeaker on a hot plateHeating iceTwo beakers side by sideRods and matchsticksBlack, white and silver cans
- Thermodynamics LabMolecular speedsSqueezing with the handwheelHeating in a water bathEnergy ledgerCarnot cycle
- Sound LabBell in a bell jarThree sound pathsRuler on a desk edgeDrum and sound meterSources and oscilloscopeUltrasonic ranging
- Vibrations and Waves LabSpring oscillatorSimple pendulumDriven oscillatorWave demonstratorStanding wave on a string
- Electricity bench (middle school)Two bulbsRheostat circuitResistance wiresKerosene flasksFuseElectromagnet
- Electricity bench (high school)Cell and rheostatSmall bulbCapacitorCoil and bulbLC circuitTransformer kit
- Electric and Magnetic Fields LabCharged spheres and probeParallel-plate capacitore/m apparatusMagnet and coilAC generator
- Optics LabOptics disc and mirrorGlass plate and candlesSemicircular glass blockLight leaving the blockOptical benchDouble slit and screenTwo polarizers
- Modern Physics LabZinc plate and electroscopePhotocellMercury lamp and filtersGold foil and microscopeHydrogen tube and spectrometerFranck–Hertz tube
Chemistry95
- The Periodic Table
- Atomic orbitals and electron cloudsElectron cloudOrbital shapesRadial distribution and nodesEnergy levels and aufbauElectron configurationQuantum numbersOrbital library
- Molecular shape labPair repulsionHide the lone pairsBond anglesHybrid orbitalsMolecular polarityExpanded octetsChiral moleculesMolecule library
- Crystal growth
- Microscopic world of reactionsEffective collisionsTemperature and activated moleculesConcentration and pressureReaching equilibriumShifting equilibriumChain reaction
- Catalyst labAnother way overThe surface cycleEquilibrium stays putSelectivityCatalyst poisoning
- Reaction mechanisms: molecular animationsAcetic acid + ethanolEthyl acetate + OH⁻Ethene + bromineEthene monomersMethane + chlorineCopper wire + ethanolEthanol + conc. H₂SO₄Benzene + bromineHCl + NaOHAgNO₃ + NaClZinc + copper sulfateSodium + waterMethane + oxygenHydrogen + chlorineAluminium + iron oxideBromoethane + OH⁻Tertiary halide + waterBromoethane + OH⁻ (in ethanol)Acetic acid + ethanol + H⁺
- Making gases in the labHeat KMnO₄Decompose H₂O₂Make CO₂ from marbleBurn charcoalBurn iron wireProperties of CO₂
- Purifying crude saltWeigh the crude saltMeasure and transfer waterAdd portions and stir gentlyStop adding and weigh what remainsFold and open the filter paperWet the paper and fit it to the wallSet up and check the two levelsFilter along the rod with three contactsTransfer the filtrate to the dishHeat and stir continuouslyExtinguish and use residual heatCool, transfer and weigh
- Chemical Analysis LabBurette and pipetteAcid–base titrationTitration curvesError analysisTesting for cationsTesting for anionsFlame testsIdentify an unknown salt
- Galvanic and Electrolytic Cells LabHofmann voltameterCopper–zinc cellSalt-bridge cellElectrolysis in a U-tubeMembrane cellPlating and refiningCorrosion tube and manometer
- Mineral cleaning and repair labFive specimensOne soft brushThree liquidsA beaker of acidOne break
- Fossil moulding and colouring labA silicone mouldA cup of plasterTwo liquids, A and BA caliperThree coats of colour
- Crystal cluster model labOne digital scaleA net that keeps growingThree silicone traysOne thin streamThree crystals, one shape
Biology15
Questions
Do I need an account or an install?
Neither. Open the page and start. Everything is free.
Does it work on a phone?
Yes. On a phone the lab controls move into a bottom drawer. Heavy 3D scenes run smoother on a computer.
Are these animations or real calculations?
Real calculations. Each lab runs a mathematical model that produces the scene and the readings live, and the model is checked numerically before release.
What level is it for?
Middle school through high school physics, chemistry and biology. Each experiment starts from an everyday question, so curious adults can follow too.
Can I use it in class?
Yes. Every experiment has its own link you can put on a projector, and you can switch between English and Chinese at any time.
Where does the data come from?
Periodic table data comes from PubChem, IAEA and NIST. Cell and apparatus models are generated in code. Physical quantities follow the textbook equations.