1. 1 Chapter 3Atoms and Elements 3.1 Classification of Matter Copyright © 2009 by Pearson Education, Inc.

2. 2 Matter Matter is the “stuff” that makes up all things. Copyright © 2009 by Pearson Education, Inc.

3. 3 A pure substance is classified as matter with a specific composition. an element when composed of one type of atom. a compound when composed of two or more elements combined in a definite ratio. Pure Substances

4. 4 Elements Elements are pure substances that contains atoms of only one type. Copper, Cu Lead, Pb Aluminum, Al Copyright © 2009 by Pearson Education, Inc.

5. 5 Compounds contain two or more elements in a definite ratio. Salt (NaCl) Table sugar (C 12 H 22 O 11 ) Water (H 2 O) Copyright © 2009 by Pearson Education, Inc.

6. 6 Elements in a Compound “Table salt” is a compound that contains the elements sodium and chlorine.

7. 7 Mixtures A mixture is a type of matter that consists of two or more substances that are physically mixed, not chemically combined. two or more substances in different proportions. substances that can be separated by physical methods.

8. 8 Physical Separation of a Mixture Example: Pasta and water are separated with a strainer. Copyright © 2009 by Pearson Education, Inc.

9. 9 Homogeneous Mixtures In a homogeneous mixture, the composition is uniform throughout. the different parts of the mixture are not visible. Copyright © 2009 by Pearson Education, Inc.

10. 10 Heterogeneous Mixtures In a heterogeneous mixture, the composition of substances is not uniform. the composition varies from one part of the mixture to another. the different parts of the mixture are visible. Copyright © 2009 by Pearson Education, Inc.

11. 11 Classification of Matter

12. 12 Identify each of the following as a pure substance or a mixture. A. pasta and tomato sauce B. aluminum foil C. helium D. air Learning Check

13. 13 Identify each of the following as a pure substance or a mixture. A. pasta and tomato saucemixture B. aluminum foilpure substance C. helium pure substance D. air mixture Solution

14. 14 Identify each of the following as a homogeneous or heterogeneous mixture: A. hot fudge sundae B. air C. sugar water D. peach pie Learning Check

15. 15 Identify each of the following as a homogeneous or heterogeneous mixture: A. hot fudge sundaeheterogeneous mixture B. air homogeneous mixture C. sugar water homogeneous mixture D. peach pie heterogeneous mixture Solution