Changes in Matter Big Idea 9 – SC.4.P.9.1 Department of Mathematics and Science Office of Academics and Transformation

Benchmark Descriptions SC.4.P.9.1 – Identify some familiar changes in materials that result in other materials with different characteristics, such as decaying animal or plant matter, burning, rusting, and cooking.

What is Matter? Matter is anything that takes up space and has weight. Matter has three forms. Matter can be a solid, a liquid, or a gas. Matter can be described by its properties. Matter is made up of tiny particles called atoms.

What do we know about solids, liquids, and gases? Solids have a definite shape and a definite volume. Liquids have definite volume but take the shape of the containers. Gases take the shape and volume of the containers.

Take a piece of paper and change it in some way. How did you change your piece of paper it? Folding Bending Tearing Cutting Crumpling Why are the changes that you made to the paper just physical changes? The paper is still paper. You can unfold it. Explore:

Physical change is often due to a change in temperature How does heat affect physical changes? Some types of matter change state when enough heat is added to it (melting) or taken away from it (freezing). What are some examples of each? Explore: Click on the hyperlink: Physical change is often due to a change in temperature and explore a FOSS site showing the effects of objects placed in the freezer. Review with students the temperature of the freezer - 0 ̊ Celsius or 32 ̊ Fahrenheit Explain and evaluate: Answer How does heat affect physical changes? Have students give examples. Water freezes at 0 ̊ Celsius or 32 ̊ Fahrenheit

More on Physical Changes What is happening to the ice cubes? They’re melting. If you add enough heat energy to ice, it turns into liquid water, then it turns into a gas called water vapor. If you cool the substance, by taking away heat energy, you can reverse these changes. You can change a gas into a liquid and a liquid into a solid. What type of change is this? Changing from one state to another state is an example of a physical change. Explore and Explain: Teacher should place ice cubes in clear plastic cups on students’ desk. Students should record observations in their science journals. Then discuss what is happening to the ice cubes.

What is a Physical Change? Crushing Folding Bending Tearing Cutting Crumbling Sanding Smashing Peeling Melting * Freezing * *Changing from one state of matter to another. EXPLAIN: click on hyperlink to watch 2:13 mins. video from Discovery Education - https://app.discoveryeducation.com/player/view/assetGuid/95388821-f7d3-4c21-83d8-34f6b6869acf

What are some physical properties of matter? Color Texture Odor Size Volume Mass Solid, Liquid, or Gas Magnetic Floats or sinks Boiling point Melting point EXPLORE: Ask students to look around the classroom and identify matter and its physical properties. Example: teacher’s desk (solid, has mass, color…etc.)

What are Physical Changes of Matter? A physical change is a change in the physical properties of matter. The matter changed in how it looks, but what it is made out of does not change. A change that takes place when a substance changes in size, shape or form. The particles of matter do not change. Explain/Evaluate: Student discuss and define what physical changes are. Ask students to write and illustrate examples of physical changes of matter.

What are Chemical Changes? ENGAGE: Click on the hyperlink to watch a 6:10 mins. Discovery Education video on Chemical Changes. Then have students look at the clip art and ask students why the pictures are examples of chemical changes.

Chemical Changes Chemical changes produce new substances that have different properties than the original substances. What are some examples of chemical changes? Burning Rusting Cooking and baking Explain/Evaluate: Student discuss and define what chemical changes are. Ask students to write and illustrate examples of chemical changes of matter.

More on Chemical Changes Fresh Leaves Decaying Leaves EXPLAIN: Have students discuss by observing the clipart. Suggest reasons: the leaves died and fell off the tree and no longer have their source of energy through photosynthesis. The dead leaves react with the oxygen in the air and break down (decompose). Why did the leaves change?

What are some examples of chemical properties? Corrosion of metal—when iron combines with oxygen in the air, rust forms Gas bubbles— Baking soda combines with vinegar, carbon dioxide forms A change in color (browning of fruit - decay) – an apple is peeled and reaction with oxygen in the air Chemical changes change the chemical nature and properties of substances to form new substances. Explain and evaluate:

What are some examples of evidence that a chemical change took place? Signs Change in odor Change in color Change in taste Change in mass Forming bubbles (giving off a gas) Giving off smoke Giving off light

Hands On Activity Big Idea 9: Changes in Matter Change in Temperature Lab Adapted from American Chemical Society Inquiry in Action Refer to Change in Temperature Lab Power Point Presentation at Science Website Instructional Resources Grade 4 Quarter 1 http://science.dadeschools.net/elem/InstructionalResources/IR-4.html Explore: Refer to Change in Temperature Lab Power Point Presentation at Science Website Instructional Resources Grade 4 Quarter 1 http://science.dadeschools.net/elem/InstructionalResources/IR-4.html Department of Science

Compare and Contrast Property Changes Physical change Chemical changes A physical change is a change in the physical properties of matter. The matter changed in how it looks, but what it is made out of does not change. A change that takes place when a substance changes in size, shape or form. The particles of matter do not change. A chemical change is a change in the chemical properties of matter. A chemical change occurs when two or more kinds of matter combine to form a new substance with different properties. A change that takes place when a substance is completely altered. The particles of matter do change. Explain and Evaluate:

Review What is a chemical change? Answer: A chemical change produces substances that have new properties. How is a chemical change different than a physical change? Answer: A physical change does not produce new substances like a chemical change does. It only changes physical properties. How is heat involved in chemical changes? Answer: Sometimes heating can cause chemical changes. Sometimes chemical changes give off heat. How is heat involved in physical changes? Answer: Sometimes adding heat to matter can change its state -when enough heat is added to it can cause melting or if heat is taken away it can cause freezing of the matter. Explain and evaluate:

Quiz: Decide if each example is a physical or chemical change. Change Scenario Physical or chemical Water boiling into steam An ice cream melting A bicycle rusting in the rain A banana turning brown Tearing paper into pieces A candle wick burning Water freezing into ice A carton of milk going sour A loaf of bread cut into slices Burning toast in the toaster 1. 2. 3. 4. 5. 6. 7. 8 9. 10. Evaluate: Quiz

Chemical Change Resources: Free Brain POP: Matter Changing Property Changes Scholastic Study Jams: Physical & Chemical Changes of Matter CHEM4KIDS: Changing States of Matter Chemical Reactions Discovery Education Science Content: Exploration: Chemical Changes Reading Passage: Keep it in the Dark Video: Chemical Changes Video: Chemical Reactions Resources