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.
Tap an atom to add it to your assembly workbench.
Essential fluid for all living organisms, covering over 70% of Earth's surface.
Atoms, chemical bonds, molecular formulas, and beginner chemistry tips.
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, or ionic compounds such as table salt.
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.
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.
Water (H2O) keeps us hydrated, Oxygen (O2) powers our muscles, Carbon Dioxide (CO2) feeds green plants, and Table Salt (NaCl) flavors our food.
Use colorful building bricks or clay balls with toothpicks at home to physically recreate the 3D structures shown on screen.
Learning how atoms assemble helps children understand that everything in the physical world has structure and order.
Free tools that often go together. Everything runs in your browser.
It is a free interactive chemistry workbench for kids and elementary students to build real molecules and learn chemical formulas through puzzles.
The tool includes Hydrogen (H), Oxygen (O), Carbon (C), Nitrogen (N), Sodium (Na), and Chlorine (Cl).
An atom is a single building block of matter, while a molecule is two or more atoms bonded together.
H2O is the chemical formula for water, consisting of 2 Hydrogen atoms chemically bonded to 1 Oxygen atom.
Table salt (NaCl) is an ionic compound: one sodium ion and one chlorine ion packed in a crystal, not a shared-electron molecule.
Practice mode offers three self-paced quizzes: building target molecules, formula detective matching, and counting atom quantities.
Your quiz attempts and accuracy are saved locally in your browser with no login or account required.
Complex orbital electron quantum mechanics and organic macromolecule synthesis are excluded for age-appropriate clarity.
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