Matter and Energy

1. Matter and Energy Matter Can Exist in Many States Can Be Made Up of Elements, Compounds, and Mixtures

2. Matter • Anything that hasdensity (mass and volume) • Mass is a constant property unlike weight and volume • Ex. Al, water, air , glass

3. 2.1 Describing Matter • Extensive Properties • An extensive property is a property that depends on the amount of matter in a sample. • The massof an object is a measure of the amount of matter the object contains. • The volume of an object is a measure of the space occupied by the object.

4. 2.1 Identifying Substances • Matter that has a uniform and definite composition is called a substance. These kettles are mainly copper. Copper is an example of a substance.

5. 2.1 Describing Matter • Intensive Properties • An intensive property is a property that depends on the type of matter in a sample, not the amount of matter. • The hardness of a bowling ball is an example of an intensive property.

6. Divisions of Matter • Pure Substance • All matter that has is homogeneous (containing the same composition of material throughout the sample (uniform) • cannot be separated physically • ie elements and compounds • water, oxygen, sugar

7. Matter and Energy Element: A substance that cannot be decomposed by any chemical reaction into simpler substances. Made up of atoms Compound: A substance made up of elements chemically combined to each other and can be decomposed by chemical means Are in a fixed proportion

8. Law of Conversation of Matter • In any physical or chemical reaction, mass is neither created nor destroyed; it is conserved • 18g H2O 16gO2 + 2gH2

9. Mixture • Mixture (not a substance) • Combinations oftwo or more pure substancesthat are not chemically combined together canbe separated by physical means ( not a fixed conposition) • Retains its individual properties • coffee ground, salt water

10. 2.2 Classifying Mixtures • A mixture is a physical blend of two or more components. • A salad bar provides a range of items. Customers choose how much of each item to use in their salads. Each salad has a different composition.

11. Types of Mixtures • Homogeneous • Material has a uniform composition throughout (particles are evenly mixed) Another name for a homogeneous mixtureis a solution. • Heterogeneous • Materials withvarying composition(parts are not uniformly mixed or dispersed)

12. 2.2 Classifying Mixtures • When oil and vinegar are mixed they form layers, or phases. The oil phase floats on the water phase.

13. Types of Mixtures • Variable combination of 2 or more pure substances. Heterogeneous –visibly separate phases Homogeneous – Same throughout

14. 2.1 Identifying Substances

15. 2.1 Physical Changes • During a physical change, some properties of a material change, but the composition of the material does not change. • As gallium melts in a person’s hand, the shape of the sample changes, but the composition of the material does not change.

16. 2.3 Distinguishing Elements and Compounds • Breaking Down Compounds • A chemical change is a change that produces matter with a different composition than the original matter. • When table sugar is heated, it goes through a series of chemical changes.

17. 2.3 Distinguishing Elements and Compounds • The final products of these chemical changes are solid carbon and water vapor. The following diagram summarizes the process.

18. 2.3 Distinguishing Elements and Compounds • Compounds can be broken down into simpler substances by chemical means, but elements cannot.

19. 2.3 Distinguishing Elements and Compounds • Chlorine is used to kill harmful organisms in swimming pools.

20. 2.3 Distinguishing Elements and Compounds • Sodiumis stored under oil to keep it from reacting with oxygen or water vapor in the air. Sodium vapor produces the light in some street lamps.

21. 2.3 Distinguishing Elements and Compounds • Sodium Chloride (commonly known as table salt) is used to season or preserve food.

22. MIXTURE PURE SUBSTANCE yes Is the composition uniform? no yes no Can it be chemically decomposed? http://youtu.be/Tm-M4OFSaCU Matter Flowchart MATTER no yes Can it be physically separated? Homogeneous Mixture Aka (solution) Heterogeneous Mixture Element Compound Physical Properties Used to Describe Matter Extensive - depends on the amount of matter in a sample. Ex. Mass and volume Intensive - depends on the type of matter in a sample, not the amount of matter. Ex. Hardness, color

23. 2.1 States of Matter • Three states of matter are solid, liquid, and gas.

24. 2.1 States of Matter • Solids • A solid is a form of matter that has a definite shape and volume. • Geometric shape • Crystalline structure • Strong Intermolecular forces (IMF)

25. 2.1 States of Matter • Liquid • A liquid is a form of matter that has an indefinite shape, flows, yet has a fixed volume. • Intermediate IMF

26. 2.1 States of Matter • Gases • A gas is a form of matter that takes both the shape and volume of its container. • Weak Intermolecular force • Indefinite shape and volume

27. 2.1 States of Matter • Vapor describes the gaseous state of a substance that is generally a liquid or solid at room temperature, as in water vapor. • H20 (g) water vapor • I2 (g) Iodine vapor

28. 2.1 Identifying Substances • A physical property is a quality or condition of a substance that can be observed or measured without changing the substance’s composition. • Used in identification of the substance • Hardness, color, conductivity, and malleability are examples of physical properties. • Properties of metals • Ductile • Malleable • Conducts electricity

29. 2.1 Physical Changes • During a physical change, some properties of a material change, but the composition of the material does not change. • As gallium melts in a person’s hand, the shape of the sample changes, but the composition of the material does not change.

30. 2.1 Physical Changes • Physical changes can be classified as reversible or irreversible. • All physical changes that involve a change from one state to another are reversible. • Boiling, freezing, melting condensing • Cutting hair, filing nails, and cracking an egg are examples of irreversible physical changes.

31. Chemical Properties • Characteristic that describes how the substance interacts or fails to interact with other substances to produce a new substance • 4Fe(s) + 3 O2 (g) 2Fe2O3 (s) • Corrosion or rusting

32. Separating Mixtures • The following properties can be used to separate mixtures • Density • Molecular polarity • Freezing point • Boiling point

33. Separation Techniques 1. Filtration 2. Chromatography 3. Distillation distillation

34. 2.2 Separating Mixtures 1. Filtration • The process that separates a solid from the liquid in a heterogeneous mixture is called filtration. • A colander is used to separate pasta from the water in which it was cooked. This process is a type of filtration. • Filtration Separation Techniques • http://ed.ted.com/lessons/the-science-of-macaroni-salad-what-s-in-a-mixture-josh-kurz

35. 2.2 Separating Mixtures 2. Chromatography • Components in a mixture are separated due to their attraction to the medium (paper) and travel at different rates. • http://www.kentchemistry.com/links/Matter/separation.htm

36. 2.2 Separating Mixtures 3. Distillation **used to separate solids dissolved in liquids **used to separate miscible liquids that have different boiling points • During a distillation, a liquid is boiled to produce a vapor that is then condensed into a liquid. • www.youtube.com/watch?v=xxNfJLMNS4E

37. Fractional Distillation: www.youtube.com/watch?v=26AN1LfbUPc