Physical Properties of Matter

Since almost everything around us is one type of matter or another, people need ways to better describe these types and help tell the different kinds of matter apart. At first, people used physical properties such as texture, color, and hardness. Later, they also started to use chemical properties.

Definition of Physical Properties Characteristics of matter that can be observed or measured without changing the matter’s identity

Physical properties can often be identified by using your five senses…… Taste Touch Sight Smell Hearing

Key Words Used to Identify Physical Properties State (solid, liquid, or gas) Color Hardness Heaviness (weight) Odor (smell) Mass Texture (smooth or bumpy) Volume (how much space it takes up)

If mass and volume are physical properties, then The density of matter is a physical property.

Helpful Hint: To help remember these eight physical properties, use the sentence “Some Crazy Hopping Hippos On M.T.V.

Physical Changes

Physical Change A change that affects one or more physical properties of a substance. A change in the form of a substance that does not change its identity. A change of matter from one form to another without a change in chemical properties.

Physical Changes No new substance is formed The matter may change its: State (solid, liquid, or gas) Size Shape

For example, freezing liquid water to form solid ice does not change the water chemically. Each molecule of water is still made of two hydrogen atoms and one oxygen atom. Ice is safe to eat just as water is safe to drink. The state of water may have changed, but the matter has not changed. Changes of state or physical changes usually happen by adding or taking away heat.

Examples: Steel melting Ice melting Ice cream melting to milk Sweat evaporating off to cool you

Freezing (liquid to solid) When energy is taken away from a liquid, the particles slow down and don’t move around much becoming a solid. Freezing is the opposite of melting!

Note: Sometimes a gas will turn directly into a solid without becoming a liquid. This change is important to weather because this is how snow crystals form!

Physical Changes Do Include: Dissolving

Physical Changes Do Not : Form new substances Burn Rot Produce a Gas Rust