1. 2.1 Properties of Matter > 1 Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Unit 2: Ch. 2 Matter and Change

2. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. “Do Now” Complete a Venn diagram to compare and contrast copper and aluminum.

3. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Section 2.1 Why do all samples of a substance have the same intensive properties?

4. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Describing Matter What you observe when you look at a particular sample of matter is its properties. Properties used to describe matter can be classified as extensive or intensive properties.

5. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. extensive property - depends on the amount of matter in a sample e.g., mass and volume intensive property - depends on the type of matter in a sample e.g., absorbancy, boiling point, melting point

6. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Identifying a Substance (pure) substance-Matter that has a uniform and definite composition Every sample of a given substance has identical intensive properties because every sample has the same composition.

7. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. physical property - quality or condition of a substance that can be observed or measured without changing the substance’s composition e.g., hardness, color, conductivity, and malleability

8. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. What are the three states of matter? (Be able to compare/contrast them!) States of Matter Three states of matter are solid (s), liquid (l), and gas (g)

9. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. SOLIDLIQUIDGAS SHAPEDEFINITE-doesn’t depend on shape of container INDEFINITE-takes the shape of the container INDEFINITE VOLUMEDEFINITE INDEFINITE PARTICLES (draw in sample diagrams of particle arrangements) packed tightly together, often in orderly arrangement particles in close contact; arrangement of particles is not rigid or orderly (ability to flow) usually much farther apart than the particles in a liquid COMPRESSIONalmost incompressible easily compressed into a smaller volume EXPANSIONslightly when heated directly proportional to temperature

10. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. A substance is in a state in which it takes the shape of its container. What state or states could it be in? Liquid or a gas (each takes the shape of its container) Answer the Q in your notebook!

11. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. How can physical changes be classified? During a physical change, some properties of a material change, but the composition of the material does not change Physical changes can be classified as reversible or irreversible. Changes of state (melting, boiling, freezing, etc.) are reversible Mechanical changes (grinding, cutting, chopping, etc.) are irreversible Dissolving (salt in water, sugar in juice, etc.) are reversible

12. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Section 2.2 How can mixtures be classified? A mixture is a physical blend of two or more components Based on the distribution of their components, mixtures can be classified as heterogeneous mixtures or homogeneous mixtures.

13. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. homogeneous mixture-composition uniform throughout (also called a solution) e.g., oil, vinegar, salt water, stainless steel, air consist of a single phase

14. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. heterogeneous mixture-composition is not uniform throughout e.g., sand, chicken soup, oil and vinegar mixed together consists of two or more phases

15. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. How can mixtures be separated? Differences in physical properties can be used to separate mixtures Filtration-(physical property of size)-separates solid from liquid in a heterogeneous mixture Distillation-(physical property of boiling point)- separates liquids from other liquids (or solids dissolved in liquids) in a homogeneous mixture

16. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Section 2.3 How are elements & compounds different?

17. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Substances can be classified as elements or compounds element - simplest form of matter that has a unique set of properties Represented by a 1- or 2-letter chemical symbol –First letters are capitalized –When a second letter is used, it is lowercase.

18. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. compound - a substance that contains two or more elements chemically combined in a fixed proportion Chemical symbols provide a shorthand way to write chemical formulas of compounds Subscripts in chemical formulas tell you how many of each type of element are in the compound Compounds can be broken down into simpler substances by chemical means, but elements cannot

19. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. How can substances and mixtures be distinguished? If the composition of a material is fixed, the material is a substance. If the composition of a material may vary, the material is a mixture.

20. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved..

21. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. No matter what you do to a silvery liquid, it doesn’t seem to change. Is it more likely to be a substance or a mixture? It is most likely a substance. If it was a mixture, it would likely have separated when manipulated chemically or physically. Answer the Q in your notebook!

22. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Why is a periodic table useful? All the known elements are organized in a special table called the periodic table. periodic table - arrangement of elements in which the elements are separated into groups based on a set of repeating properties Allows you to compare the properties of one element (or a group of elements) to another

23. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Each element is identified by its symbol placed in a square (“faceplate”) Elements are listed in order from left to right and top to bottom by atomic number Element name Atomic number Element symbol Atomic mass

24. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Each horizontal row of the PT is called a period There are 7 periods Each vertical column of the periodic table is called a group, or family. There are 18 groups Elements within a group have similar chemical and physical properties

25. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Section 2.4 Chemical Reactions What always happens during a chemical change? The ability of a substance to undergo a specific chemical change is called a chemical property Can be used to identify a substance but can be observed only when a substance undergoes a chemical change During a chemical change, the composition of the substance always changes

26. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. A chemical change is also called a chemical reaction One or more substances change into one or more new substances during a chemical reaction Reactant – substance present at the start of the reaction Product – substance produced in the reaction C + O 2  CO 2

27. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Recognizing Chemical Changes Possible clues to chemical change include... 1.transfer of energy, 2.change in color, 3.production of a gas, 4.or the formation of a precipitate-a solid that forms and settles out of a liquid mixture.

28. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Every chemical change involves a transfer of energy. BE CAREFUL-The only way to be sure that a chemical change has occurred is to test the composition of a sample before and after the change

29. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Are the changes that happen to a burning match chemical or physical changes? How do you know? A burning match is undergoing a chemical change. There is a transfer of heat, a production of light, and a change of color. The composition of the materials also changes during the burning process. Answer the Q in your notebook!

30. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. Conservation of Mass How are the mass of the reactants and the mass of the products of a chemical reaction related? During any chemical reaction, the mass of the products is always equal to the mass of the reactants. NOTE: Mass also holds constant during physical changes.

31. Copyright © Pearson Education, Inc., or its affiliates. All Rights Reserved.. The law of conservation of mass states that in any physical change or chemical reaction, mass is conserved. Mass is neither created nor destroyed. The law of conservation of mass is more easily observed when a change occurs in a closed container.