Science

Explore how the world works, and see how much of it you already know.

General Science
A broad first look across chemistry, biology, physics, and astronomy.
Introduction to Chemistry
Atoms, elements, and the basic reactions that hold matter together.
Easy
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Human Biology Basics
How the body’s major systems work, from the heart to the brain.
Easy
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Physics: Forces & Motion
Newton’s laws, gravity, and the physics of everyday motion.
Medium
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The Periodic Table
Elements, groups, and the logic behind the periodic table’s layout.
Medium
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Astronomy & the Solar System
Planets, moons, and the scale of our cosmic neighborhood.
Easy
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Biology
Cells, genes, evolution, ecosystems, and the human body — the fundamentals of life science.
Cell Biology
Membranes, organelles, mitosis and meiosis — the machinery inside every living cell.
Medium
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Genetics & DNA
Base pairing, alleles, and Mendelian crosses — the code that builds every organism.
Medium
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Evolution & Natural Selection
Darwin, adaptation, and the evidence behind how species change over time.
Medium
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Ecology & Ecosystems
Food chains, biomes, and how energy flows through a living system.
Easy
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Photosynthesis
Light reactions, the Calvin cycle, and how plants turn sunlight into sugar.
Medium
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Animal Kingdom Classification
Taxonomic ranks, vertebrate classes, and what separates one phylum from another.
Easy
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Plant Biology
Roots, xylem, stomata, and how plants move water, food, and light-response signals.
Easy
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Human Nervous System
Neurons, synapses, and the wiring behind thought, reflex, and movement.
Medium
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Human Digestive System
From the esophagus to the small intestine — how your body breaks down food.
Medium
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Human Cardiovascular System
Heart chambers, blood vessels, and how oxygen actually reaches your tissues.
Medium
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Human Immune System
Innate vs. adaptive defense, antibodies, and how vaccines train the system.
Hard
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Human Skeletal & Muscular System
Bones, joints, and the muscle types that hold you up and move you around.
Easy
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Microbiology
Bacteria, viruses, and fungi — the microscopic life that shapes health and disease.
Hard
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Chemistry
Bonds, reactions, and the matter itself — how atoms combine, react, and mix.
Chemical Bonds
Ionic, covalent, and metallic bonds — how atoms actually hold onto each other.
Medium
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Acids & Bases
pH, neutralization, and the Brønsted-Lowry definitions behind every acid-base reaction.
Medium
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Organic Chemistry Basics
Hydrocarbons, functional groups, and the carbon chemistry behind every living thing.
Hard
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States of Matter
Solids, liquids, gases, and the phase changes that move between them.
Easy
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Chemical Reactions & Equations
Balancing equations and telling synthesis, decomposition, and combustion apart.
Medium
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Mixtures & Solutions
Solutes, solubility, and the difference between a solution, a suspension, and a colloid.
Medium
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Enzymes & Metabolism
Active sites, ATP yield, and how enzymes speed up the reactions that keep cells alive.
Hard
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Physics
Forces, energy, waves, and the rules governing everything from circuits to spacetime.
Thermodynamics Basics
Energy, entropy, and the laws that govern heat, work, and why processes go one way.
Hard
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Electricity & Circuits
Ohm's Law, series vs. parallel, and how current actually moves through a circuit.
Medium
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Magnetism
Poles, fields, and how electricity and magnetism turn out to be the same force.
Easy
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Light & Optics
Reflection, refraction, and lenses — how light behaves and how we bend it on purpose.
Medium
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Sound & Waves
Frequency, amplitude, and the Doppler effect — the physics behind everything you hear.
Medium
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Nuclear Physics Basics
Isotopes, decay, and the forces holding — or splitting — the atomic nucleus.
Hard
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Quantum Mechanics Introduction
Superposition, uncertainty, and entanglement — the strange rules governing the very small.
Hard
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Special Relativity Basics
Time dilation, length contraction, and why nothing outruns the speed of light.
Hard
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Gravity & Orbital Mechanics
Kepler's laws, escape velocity, and what actually keeps a satellite in orbit.
Medium
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Earth & Space
From tectonic plates and ocean currents to black holes and exoplanets — the planet and the universe around it.
Climate & Weather
The greenhouse effect, ocean currents, and what actually shapes local weather.
Medium
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Plate Tectonics & Earthquakes
Plate boundaries, seismic waves, and why the Ring of Fire earns its name.
Medium
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Rocks & Minerals
Igneous, sedimentary, metamorphic — and the Mohs scale that ranks their hardness.
Easy
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The Water Cycle
Evaporation, condensation, and how the same water keeps circulating the planet.
Easy
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Oceans & Marine Biology
Coral reefs, deep-sea adaptations, and the currents that move an entire ocean.
Medium
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Environmental Science & Climate Change
Carbon footprints, the Paris Agreement, and the science behind a warming planet.
Medium
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Renewable Energy
Solar, wind, hydro, and geothermal — how each one actually generates power.
Medium
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The Electromagnetic Spectrum
Radio waves to gamma rays — one spectrum, wildly different uses and risks.
Hard
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Black Holes & Neutron Stars
Event horizons, pulsars, and the extreme physics left behind by dying stars.
Hard
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Galaxies Beyond the Milky Way
Spiral, elliptical, and irregular — the shapes and history of galaxies beyond our own.
Medium
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Exoplanets & Habitable Zones
The Goldilocks zone, detection methods, and the hunt for another livable world.
Medium
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Space Exploration History
Sputnik to the ISS — the milestones that took humanity off the planet.
Easy
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Exam Prep
Chemistry, physics, and biology practice built for JEE Main and NEET — the formulas, mechanisms, and units these exams actually test.
Inorganic Chemistry Exceptions
Where the periodic table breaks its own rules — lithium, gallium, fluorine, and the exceptions JEE Main loves to test.
Hard
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Chemical Bonding & VSEPR
Molecular geometry, hybridization, and why NH₃ and NF₃ don't behave the way you'd expect.
Hard
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Coordination Compounds
Werner's theory, isomerism types, and why [Ni(CN)₄]²⁻ and [NiCl₄]²⁻ behave so differently.
Hard
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Equilibrium & Le Chatelier's Principle
Pressure, temperature, inert gases, and catalysts — what actually shifts an equilibrium and what doesn't.
Hard
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Electrochemistry
Why lithium — not potassium — is the strongest reducing agent, and why brine electrolysis gives chlorine, not oxygen.
Hard
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Organic Reaction Mechanisms
SN1 vs. SN2, Markovnikov vs. the peroxide effect, and the one halogen exception in aromatic substitution.
Hard
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Mechanics & Newton’s Laws
Newton’s three laws, friction, momentum, and work-energy — JEE Main mechanics in one focused quiz.
Hard
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Electromagnetism & Circuits
Ohm’s law, Coulomb’s law, Faraday’s and Ampère’s laws — JEE Main electricity and magnetism.
Hard
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Optics & Wave Phenomena
Snell’s law, lenses, interference, and diffraction — JEE Main optics in one quiz.
Hard
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Thermodynamics & Kinetic Theory
The gas laws, heat capacities, and entropy — JEE Main thermodynamics and kinetic theory.
Hard
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Modern Physics: Atomic & Nuclear
Bohr’s model, the photoelectric effect, and radioactive decay — JEE Main modern physics.
Hard
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Rotational Motion & Gravitation
Moment of inertia, angular momentum, and Kepler’s laws — JEE Main rotation and gravitation.
Hard
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Human Reproduction
Gametogenesis, the menstrual cycle, and fertilization — NEET’s Human Reproduction unit.
Medium
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Biotechnology
Restriction enzymes, PCR, and recombinant insulin — NEET’s Biotechnology unit.
Medium
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Animal Tissues
Epithelial, connective, muscular, and nervous tissue — NEET’s Structural Organisation unit.
Medium
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Plant Kingdom Classification
Algae to angiosperms — NEET’s Plant Kingdom classification unit.
Medium
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Human Health & Diseases
Immunity, pathogens, cancer, and substance abuse — NEET’s Human Health unit.
Medium
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Excretory System
The nephron, urine formation, and osmoregulation — NEET’s Excretory System unit.
Medium
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AP Biology: Cellular Respiration
Glycolysis, the Krebs cycle, the electron transport chain, and where the ATP actually comes from.
Hard
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AP Biology: Hardy-Weinberg Equilibrium
Allele frequencies, the five conditions, and the calculations the exam actually asks for.
Hard
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AP Chemistry: Stoichiometry
Mole ratios, limiting reactants, percent yield, and empirical formulas.
Hard
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AP Chemistry: Reaction Kinetics
Rate laws, reaction order, half-life, and activation energy.
Hard
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