Unit 2 Chemistry Lesson 4 Changes in Matter Essential Questions: 1 Unit 2 Chemistry Lesson 4 Changes in Matter Essential Questions: 1.) What happens to a substance in a physical change? 2.) What happens to a substance in a chemical change? 3.) How are changes in energy and matter related?

What happens to a substance in a physical change? A change that alters the form Physical change or appearance of matter but does not turn the substance into a different substance A butter artist has changed a block of butter into artwork.

Examples of physical change Matter exists as a liquid, States of matter solid or gas 1.) Changes of state From a solid to a liquid (melting) From a liquid to a solid (freezing) From a liquid to a gas (evaporation)

A liquid puddle of water can change into water vapor (a gas) and mix with the air. Snow can change into water (a liquid) by melting.

2.) Changes in shape or form Dissolving Bending Crushing Breaking Chopping If you pour a sugar solution into a pan (sugar and water) and let the water dry out the sugar will remain as a crust. The crust is still sugar even though it looks different.

What happens to a substance in a chemical change? A change in matter that Chemical change produces one or more new substances 1.) A single substance breaks down into two or more substances 2.) Two or more substances combine to form different substances

1.) A single substance breaks down into two or more substances Hydrogen peroxide breaks down into water and oxygen gas when it’s poured on a cut. 2.) Two or more substances combine to form different substances Several compounds combine with energy from the sun to produce new substances in photosynthesis.

Examples of chemical change Burning

What type of chemical change is occurring?