Physical Science – S 1., S1.a., S 1.b.

Students learn that materials come in different forms—solids, liquids, and gases— and observe the different properties of each form. They know that solids are rigid while liquids and gases conform to the shape of the vessel that contains them.

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Introduction to Psychology

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The Three States of Matter Defined

The Three State of Matter – Vocabulary & Definitions

What is matter?

Matter is what all living and non-living things are made of. All matter takes up space and has mass. Matter exists in three separate phases: solid, liquid, or gas.

What is a solid?

A solid is a substance that retains its size and shape without a container; a substance whose molecules cannot move freely except to vibrate.

What is a liquid?

A liquid is a substance that flows and keeps no definite shape because its molecules are loosely packed and constantly moving. It takes the shape of its container but maintains constant volume.

What is a gas?

A gas is a substance that can only be contained if it is fully surrounded by a container (or held together by gravitational pull); a substance whose molecules have negligible intermolecular interactions and can move freely.

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Video: The Three States of Matter

Power Point: The Three States of Matter

Visual Examples

Video: The Three States of Matter Song

A song for content review.

The "Big Question"

So now that you know what the three states of matter are, can you identify one example of a solid, a liquid, and a gas within your classroom?