Changes in the State of Matter

• Changes in the state of matter occur when energy is added to or removed from a substance, causing its particles to rearrange and transition between solid, liquid, and gas phases.

These transitions include:

Melting:

• Solid to liquid.

• Occurs when a solid absorbs heat, causing its particles to vibrate more until they break free from their fixed positions.

• Example: Ice melting into water.

Freezing:

• Liquid to solid.

• Happens when a liquid loses heat, causing particles to slow down and settle into fixed positions.

• Example: Water freezing into ice.

Vaporization:

• Liquid to gas.

• Occurs in two forms: evaporation (surface molecules gain enough energy to become gas) and boiling (entire liquid reaches boiling point).

• Example: Water boiling into steam.

Condensation:

• Gas to liquid.

• Gas particles lose energy, slow down, and form a liquid.

• Example: Steam condensing into water droplets.

Sublimation:

• Solid to gas without becoming a liquid.

• Example: Dry ice (solid CO₂) turning directly into gas.

Deposition:

• Gas to solid without becoming a liquid.

• Example: Frost forming on a cold surface.