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Explore Molecules & Atoms

Discover the tiny building blocks that make up everything in the universe. Snap atoms together on the workbench to create water, oxygen, and salt, learn chemical formulas, and test your knowledge with fun chemistry puzzles.

Chemical Elements Palette

14

Tap an element to add it to your assembly workbench.

2D Assembly Workbench3 atoms placed
OClick to remove this atomHClick to remove this atomHClick to remove this atom
💧
H₂OMolecule Formed!Molecule

Water

Essential fluid for all living organisms, covering over 70% of Earth's surface.

Did you know? Water is one of the very few natural substances that expands when it freezes into ice.

Discoverable Molecules & Recipes

How to explore Molecules & Atoms

Atoms, chemical bonds, 2D molecular geometry, and beginner chemistry tips.

1Atoms as nature's building blocks

Everything around us, from the air we breathe to the water we drink, is built from tiny particles called atoms. When atoms link together, they form molecules.

2Chemical bonds and valence

Different atoms have different numbers of hands or bonds to hold onto others: Hydrogen has 1 bond, Oxygen has 2, Nitrogen has 3, and Carbon has 4.

3Reading chemical formulas

The small number (subscript) tells you how many atoms of that type are present. In H2O, the 2 means two Hydrogen atoms connected to one Oxygen atom.

4Everyday molecules in our lives

Water (H2O) keeps us hydrated, Oxygen (O2) powers our muscles, Carbon Dioxide (CO2) feeds green plants, and Table Salt (NaCl) flavors our food.

5Tips for parents and teachers

Use colorful building bricks or clay balls with toothpicks at home to physically recreate the 2D structures shown on screen.

6Curiosity and scientific thinking

Learning how atoms assemble helps children understand that everything in the physical world has structure and order.

More in this lesson

Next labs in this group. Everything runs in your browser.

  • Learning toolsExplore the Water CycleInteractive water cycle diagram. Explore evaporation, condensation, precipitation, and collection with weather simulations and quizzes
  • Learning toolsExplore Magnets & PolesInteractive magnet science lab. Test North and South poles attracting and repelling, and test which household materials stick to magnets
  • Learning toolsExplore Food ChainsInteractive food chain explorer across forest, ocean, and savanna biomes. Learn producers, consumers, apex predators, and energy flow
  • Learning toolsExplore Plant Life & PhotosynthesisInteractive plant science lab. Discover roots, stems, leaves, flowers, seeds, and the photosynthesis solar kitchen with interactive puzzles
  • Learning toolsExplore Color MixingInteractive color mixing lab. Explore paint pigment mixing and additive RGB light beams with recipes and puzzles
  • Learning toolsExplore the Human BodyInteractive human body anatomy. Explore vital organs, skeletal systems, and the 5 senses with games and facts

How to use this tool

  1. Choose Explore to snap atoms into molecules or Practice for chemistry quiz games.
  2. In Explore, tap atoms across Life, Minerals, and Gas categories to add them to the workbench.
  3. Watch 2D chemical bonds connect atoms as you build valid molecules.
  4. Unlock the molecule card with structure diagrams, real-world roles, and fun facts.
  5. In Practice, try Build a Molecule to assemble the exact chemical recipe requested.
  6. Play Formula Detective to match formulas like NaCl or CO2 to their common names.
  7. Test your observation in Count the Atoms to identify atom quantities in each molecule.

Frequently asked questions

What is Explore Molecules & Atoms?▾

It is a free interactive chemistry workbench for beginners to build real molecules and learn chemical formulas through puzzles.

What chemical elements are included in this lab?▾

The lab includes 14 curated elements: Hydrogen, Carbon, Nitrogen, Oxygen, Phosphorus, Sulfur, Sodium, Chlorine, Potassium, Calcium, Magnesium, Iron, Fluorine, and Helium.

What is the difference between an atom and a molecule?▾

An atom is a single building block of matter, while a molecule is two or more atoms bonded together.

What does H2O stand for?▾

H2O is the chemical formula for water, consisting of 2 Hydrogen atoms chemically bonded to 1 Oxygen atom.

What is table salt made of?▾

Table salt (NaCl) is made of 1 Sodium (Na) atom and 1 Chlorine (Cl) atom joined by an ionic bond.

How do the practice quiz games work?▾

Practice mode offers three self-paced quizzes: building target molecules, formula detective matching, and counting atom quantities.

Where is practice progress saved?▾

Your quiz attempts and accuracy are saved locally in your browser with no login or account required.

What is simplified for elementary learners?▾

Complex orbital electron wave equations and organic reaction thermodynamics are simplified for intuitive visual understanding.

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