Unit 9 Lesson 4 What Are Some Changes to Matter? Copyright © Houghton Mifflin Harcourt Publishing Company 1

Unit 9 Lesson 4 What Are Some Changes to Matter? Physical Changes A change to matter can either be physical or chemical. Copyright © Houghton Mifflin Harcourt Publishing Company 2

Unit 9 Lesson 4 What Are Some Changes to Matter? Physical Changes In a physical change, the kind of matter all stays the same. Folding, tearing, and cutting are all examples of physical changes. Copyright © Houghton Mifflin Harcourt Publishing Company 3

Unit 9 Lesson 4 What Are Some Changes to Matter? Chemical Changes How are chemical changes different from physical changes? In a chemical change, new kinds of matter are formed. Some chemical changes can be reversed using chemical means. But most of the chemical changes you see cannot be reversed. Copyright © Houghton Mifflin Harcourt Publishing Company 4

Chemical Changes Chemical changes happen all around you. Unit 9 Lesson 4 What Are Some Changes to Matter? Chemical Changes Chemical changes happen all around you. Chemical changes can happen in your body. Suppose you eat a pear. As your body digests the pear, chemical changes break it up into simpler pieces that your body can use. Copyright © Houghton Mifflin Harcourt Publishing Company 5

Physical changes Vs. Chemical Changes Unit 9 Lesson 4 What Are Some Changes to Matter? Physical changes Vs. Chemical Changes Copyright © Houghton Mifflin Harcourt Publishing Company 6

Physical change Vs.Chemical Changes Unit 9 Lesson 4 What Are Some Changes to Matter? Physical change Vs.Chemical Changes Copyright © Houghton Mifflin Harcourt Publishing Company 7

Physical change Vs.Chemical Changes Unit 9 Lesson 4 What Are Some Changes to Matter? Physical change Vs.Chemical Changes Copyright © Houghton Mifflin Harcourt Publishing Company 8

Physical change Vs.Chemical Changes Unit 9 Lesson 4 What Are Some Changes to Matter? Physical change Vs.Chemical Changes Before After Copyright © Houghton Mifflin Harcourt Publishing Company 9

Mixtures and Solutions Unit 9 Lesson 4 What Are Some Changes to Matter? Mixtures and Solutions A mixture is two or more substances that are combined without changing any of them. Because no new matter is formed, making a mixture is a physical change. Copyright © Houghton Mifflin Harcourt Publishing Company 10

Mixtures and Solutions Unit 9 Lesson 4 What Are Some Changes to Matter? Mixtures and Solutions A solution is a mixture in which all the substances are evenly mixed. To make a solution, you completely mix, or dissolve, one substance in another. Copyright © Houghton Mifflin Harcourt Publishing Company 11

Mixtures and Solutions Unit 9 Lesson 4 What Are Some Changes to Matter? Mixtures and Solutions Copyright © Houghton Mifflin Harcourt Publishing Company 12

Mixtures and Solutions Unit 9 Lesson 4 What Are Some Changes to Matter? Mixtures and Solutions All solutions are mixtures. Lemonade is a mixture of water, sugar, and lemon juice. Lemonade is also a solution because the sugar and lemon juice have dissolved in the water. Copyright © Houghton Mifflin Harcourt Publishing Company 13

Unit 9 Lesson 4 What Are Some Changes to Matter? Properties Matter! Because making a mixture is a physical change, you can separate a mixture using the physical properties of its parts. Copyright © Houghton Mifflin Harcourt Publishing Company 14

Unit 9 Lesson 4 What Are Some Changes to Matter? Properties Matter! Floating is a physical property. You can use it to separate some mixtures. Just add water, and scoop off the objects that float. Evaporation can separate mixtures in which solids have been dissolved in liquids. As the liquid evaporates, the solids are left behind. Copyright © Houghton Mifflin Harcourt Publishing Company 15

Unit 9 Lesson 4 What Are Some Changes to Matter? Properties Matter! You can also use tools such as sieves and magnets to separate mixtures. Matter that is smaller than the holes in a sieve passes through the sieve. Matter that is larger than the holes stays on top of the sieve. Copyright © Houghton Mifflin Harcourt Publishing Company 16

Unit 9 Lesson 4 What Are Some Changes to Matter? Properties Matter! A magnet picks up matter that contains iron. A giant magnet can separate iron from plastic and other materials in a junkyard. Copyright © Houghton Mifflin Harcourt Publishing Company 17

Unit 9 Lesson 4 What Are Some Changes to Matter? Copyright © Houghton Mifflin Harcourt Publishing Company 18

Unit 9 Lesson 4 What Are Some Changes to Matter? Copyright © Houghton Mifflin Harcourt Publishing Company 19

Unit 9 Lesson 4 What Are Some Changes to Matter? Making Bagels A kitchen is filled with changes in matter as bagels are made. Hands and kitchen tools cause physical changes. Yeast and heat cause chemical changes. Copyright © Houghton Mifflin Harcourt Publishing Company 20