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Chemistry Basics: Atoms, Molecules and Reactions
A plain-language overview of chemistry: how atoms bond into molecules, how chemical reactions rearrange them, and why this explains everyday changes.
Universe and Matter
Chemistry and Materials
Reactions, everyday substances and how common materials are made.
Acids, Bases and the pH Scale
What pH actually measures, why the scale is logarithmic, and where common kitchen and lab substances such as lemon juice, baking soda and bleach fall on it.
How Fireworks Get Their Colors
Metal salts, excited electrons and carefully packed stars explain how fireworks glow red, green, blue and gold, and why some colors are harder to make.
How Glass Is Made
How sand, soda ash and lime are melted, shaped and slowly cooled into transparent glass, and why glass counts as an amorphous solid rather than a crystal.
How Soap Actually Cleans
Soap molecules have a water-loving head and a grease-loving tail, letting them lift oil and dirt from skin and disrupt some germs so water can rinse them away.
States of Matter and Phase Changes
Solids, liquids, gases and plasma differ in how particles move and interact; phase changes such as melting, boiling and sublimation move matter between them.
The Chemistry of Cooking and Baking
Browning, rising, thickening and setting are all chemical changes. See how the Maillard reaction, caramelization, leavening and protein changes shape food.
What Are Isotopes?
Isotopes are atoms of the same element with different numbers of neutrons. Learn how they differ, why some are radioactive and how they date fossils and rocks.
What Plastic Is and Why It Lasts So Long
Plastics are polymers, long chains of repeating molecules. See how they are made, why microbes struggle to break them down and how they linger in the environment.
Why Iron Rusts
Rust forms when iron reacts with oxygen and water in an electrochemical process. Learn why salt speeds it up and how paint, zinc and stainless steel slow it.
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Our Universe Space, the solar system and how we picture the cosmos. Physics and Matter Modern physics, light, the elements and everyday math. Stars and Galaxies How stars live and die and how galaxies and the early universe are understood. Planets and Space Exploration Missions, the Moon, eclipses and the search for life beyond Earth. Forces, Energy and Motion Classical physics that explains everyday motion, heat, sound and electricity.