Science Unit 5 Lesson 4: What Are the States of Water?

Vocabulary flashcards covering the states of matter, properties of water, particle behavior, and phase changes from Science Lesson 4.

States of matter

The three forms—solid, liquid, and gas—into which most matter on Earth is classified.

Solid

A state of matter that has a definite volume and shape, with particles that are close together and vibrate in place like the strings of a guitar.

Liquid

A state of matter that has a definite volume but not a definite shape, taking the shape of whatever container holds it as its particles slide past each other.

Gas

A state of matter that does not have a definite volume or shape, expanding to fill its container with particles that are far apart and move very quickly in all directions.

Water vapor

The invisible, gaseous state of water.

Particles

The tiny units that make up matter; the speed of their movement and their spacing determine the state of matter.

Change of state

The event that occurs when matter changes from one form (solid, liquid, or gas) to another.

Freezing

The change of state from a liquid to a solid when heat energy is removed, causing particles to slow down, get closer together, and lock into place.

Melting

The change of state from a solid to a liquid when heat energy is added, causing particles to speed up until they overcome the attractions holding them in place.

Evaporation

The process by which a liquid changes into a gas when heat energy is added and particles speed up enough to enter the air.

Condensation

The process by which a gas changes into a liquid when heat energy is removed, causing particles to slow down and clump together.

Clouds

Structures that form in the sky when water vapor condenses on particles of dust in the air.

Steam cleaning

A practical application and common use of water vapor identified in the lesson.