Interactive Chemistry Simulations for Students | Shikkha Web

Grade 8–11

Structure of the atom

Structure of the atom explained with an interactive simulation: protons, neutrons, electrons, atomic and mass number, isotopes and electron configuration, with solved examples.

Grade 8–11

Acids, Bases and the pH Scale

What is pH and what does the pH scale show? Drip a base into an acid, watch the indicator change colour and trace a live titration curve, with worked pH problems.

Grade 9–11

Electron configuration

How to write electron configurations: Aufbau order, Pauli and Hund rules, the Cr and Cu exceptions, ions and noble-gas shorthand. Watch electrons fill, Z 1–36.

Grade 9–11

Gas laws: Boyle, Charles, Gay-Lussac, Avogadro and PV = nRT

Push a piston and heat a gas: Boyle's, Charles's, Gay-Lussac's and Avogadro's laws, the ideal gas law PV = nRT, graphs, R values and solved problems.

Grade 8–11

What is ionic bonding, and how does a metal atom transfer electrons to a non-metal to form ions? Drop NaCl, MgO or CaCl2 into the simulation and watch charge balance derive the formula, with worked examples.

Grade 9–12

Electrolysis and Faraday’s Laws

What is electrolysis, what forms at the cathode and anode, and how does Faraday's law compute the mass deposited? Choose molten NaCl, CuSO2 or acidified water and watch, with worked examples.

Grade 9–12

Covalent Bond

What is a covalent bond? Build H₂O, NH₃, CH₄ and CO₂ atom by atom in a dot-and-cross simulation: single, double and triple bonds, lone pairs, the octet rule and bond polarity, with worked examples.

Grade 9–11

Periodic Trends

What are periodic trends? See how atomic radius, ionization energy, electronegativity and metallic character change across a period and down a group, on a heat map of the first 36 elements, with the real exceptions.

Grade 9–12

Reaction rate and collision theory

What decides how fast a reaction goes? Run a collision-theory simulation: change temperature, concentration and a catalyst, and watch the activation-energy graph and the product curve respond.

Grade 8–10

States of matter: solid, liquid, gas and the heating curve

Watch particles vibrate in a solid, slide in a liquid and fly free in a gas. A live heating curve for water, melting, boiling, latent heat, sublimation, and Q = mcΔT and Q = mL worked out.

Grade 11–12

Atomic orbitals: the shapes of s, p and d, quantum numbers and nodes

Rotate the 1s, 2s, 2p and 3d orbitals in 3D. Orbit versus orbital, the four quantum numbers, counting radial and angular nodes, subshell capacities and worked examples.

Grade 11–12

Molecular shapes and VSEPR theory: bond pairs, lone pairs and angles

Build molecules in 3D and rotate them. See how bond pairs and lone pairs set the shape, bond angle and hybridisation of CH4, NH3, H2O, PCl5, SF6 and more, with solved problems.

Grade 9–11

The mole concept: molar mass, Avogadro’s number and molar volume

What is a mole, what is Avogadro’s number, and how do you convert grams to moles to molecules? Weigh substances on a virtual balance, see 22.4 L at STP, and learn percentage composition with solved problems.

Grade 11–12

Diffusion and effusion: Graham’s law of gases

Watch ammonia and hydrogen chloride build a white ring in a tube, then race gases through a pinhole. Graham’s law of diffusion and effusion derived and solved with live numbers.

Grade 9–10

Balancing chemical equations: method, examples and practice

How do you balance a chemical equation? Change coefficients and watch the atom counts on both sides match. Five worked reactions (water, methane, rust, acid, propane) with the method and exam tips.

Grade 11–12

Chemical equilibrium: the equilibrium constant Kc and Le Chatelier’s principle

What is chemical equilibrium, how do you find Kc, and which way does a reaction shift when you change concentration, temperature or pressure? Watch the Haber process rate curves and see Le Chatelier at work.

Grade 9–12

Titration: finding an unknown concentration with a burette and an indicator

What is a titration? See how a burette and an indicator work, why the end point and equivalence point differ, and how to use V₁M₁ = V₂M₂ with the mole ratio. Run it yourself with a live pH curve.

Grade 11–12

Galvanic cell: the Daniell cell, EMF and the Nernst equation

How does a galvanic cell make electricity? See which way electrons and salt-bridge ions move in the Daniell cell, how the rod masses change, and what the standard and Nernst EMF are. Change the concentrations and watch.

Grade 9–11

Redox reactions: oxidation numbers, electron transfer and half-equations

What are oxidation and reduction, how do you find oxidation numbers, and which species is the oxidising agent? Watch electrons move in five redox reactions, with half-equations and worked examples.

Grade 10–12

Hydrocarbons: alkanes, alkenes, alkynes and structural isomers in 3D

See alkanes, alkenes and alkynes as spinning ball-and-stick models. Slide the carbon count, read the general formula and IUPAC name, and view every structural isomer of butane, pentane and hexane.

Grade 10–12

Functional groups: alcohols, aldehydes, ketones, acids, esters and amines

What is a functional group, and how do you tell an alcohol, aldehyde, ketone, acid, ester or amine apart? Explore eight organic families with IUPAC names, lab tests and worked problems.

Grade 11–12

Polymerisation: addition and condensation polymers, polythene and nylon

What is a polymer, and how do addition and condensation polymerisation differ? Watch ethene become polythene and nylon-6,6 form, with chain molar masses and water released worked out.

Grade 9–11

Separation techniques: filtration, distillation, chromatography, crystallisation

Watch filtration, simple and fractional distillation, paper chromatography and crystallisation run. Compute Rf, read the boiling-point plateaus and work out crystal yield.

Grade 11–12

Crystal lattice: SC, BCC and FCC unit cells, packing efficiency and density

Rotate the simple, body-centred and face-centred cubic unit cells. Count atoms per cell, coordination number, packing efficiency (52.4%, 68%, 74%) and density.

Grade 11–12

Radioactivity: Alpha, Beta, Gamma Decay and Half-Life

Watch alpha, beta and gamma decay change A and Z, build balanced nuclear equations and see 100 atoms decay at random along the half-life curve, with a carbon-14 dating example. Free simulation.