Chemistry · Chapter 01

💧 States of Matter

Solid, liquid, gas — and how they change.

💡 Solid, Liquid, Gas

Matter exists in three main states — and the difference is just how its particles behave:

• Solid — particles are packed tightly and only vibrate in place. Fixed shape, fixed volume. (Ice 🧊)
• Liquid — particles are close but can slide. Takes the shape of its container, fixed volume. (Water 💧)
• Gas — particles fly around freely with lots of empty space. No fixed shape or volume. (Steam ☁️)

Heating gives particles energy — they move faster. Melting (solid→liquid), boiling (liquid→gas). Cool them and they slow down — condensation and freezing.

Phase diagram of water — solid, liquid, gas regionsWikimedia Commons / CC BY-SA 3.0

Dry ice sublimating — solid CO₂ directly to gas (sublimation)Wikimedia Commons / CC BY-SA 3.0

🎬

Particles in Each State

Animation

Solid particles vibrate in place. Liquid particles drift. Gas particles fly. Same matter, different energies.

🧪

Heat It Up

Experiment

Pick the temperature of water — see what state it's in.

Temperature25°C

State of water💧 Liquid

Water freezes at 0°C (ice) and boils at 100°C (steam).

Atomic Structure

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