CH. 3 Matter- Properties and Changes

1. CH. 3Matter- Properties and Changes

2. Monday • Physical and Chemical Change • Worksheet

3. 3.2 Changes in MatterTEKS • (8) Science concepts. The student can quantify the changes that occur during chemical reactions. The student is expected to: • E. Determine mass relationships between reactants and products

4. 3.1 Properties of Matter • Substance - composition is uniform, does not change between samples and is “pure”. • Pure substances: 1. Elements – Na, H, He 2. Compounds – NaCl (salt) H2O (water)

5. 3.2 Changes in Matter • Physical Change- changes which alter a substance without changing the composition. • (Does not change the identity of the substance) • Ex: ice to water

6. Examples of Physical Changes • Change in Size or Shape such as: Bend, break, cut, grind, crumple, split, or crush • Change in State such as: Melting, freezing, vaporization, boiling, condensation, or sublimation

7. Chemical Change- involves one or more substances changing into another substance • (also called a Chemical Reaction) Ex: steel to rust

8. Chemical Reactions • The new substances formed in the reaction have different compositions and different properties from the substances present before the reaction occurred.

9. Reactant – starting material in a reaction • Product – ending material in a reaction Reactant(s)  turn into Product(s) • Na + Cl = NaCl (Salt)

10. Examples of Chemical Changes • Fermentation, • rusting, • explode, • oxidize, • corrode, • tarnish, • burn, • or rot.

11. C. Conservation of Mass – By carefully measuring the mass before and after many chemical reactions, it was observed that the total mass involved in the reaction stayed the same. • Law of Conservation of Mass- states that matter is neither created nor destroyed during a reaction– it is conserved

12. Total mass of the reactants must equal the total mass of the products.Massreactants = Massproducts 4. According to the law of conservation of mass, how much zinc was present in the zinc carbonate? A 40 g B 88 g C 104 D 256 g

13. Antoine Lavoisier used an analytical balance to help prove this law.

14. Conservation of Mass problems • Ex: 23 g of Na reacts with 35 g of Cl, what is the mass of the product, sodium chloride? • 23 g Na+ 35 g Cl = ______ g NaCl Ex: #2 • 10 g HgO = 9.26 g Hg + _____ g of O

15. Tuesday • Lab on Physical and Chemical Change

16. Wednesday • Screaming gummi bears demo • Answer follow-up questions • Physical and Chemical properties matter

17. TEKS • (4) Science concepts. The student knows the characteristics of matter and can analyze the relationships between chemical and physical changes and properties. • The student is expected to: • (A) differentiate between physical and chemical changes and properties; • (B) identify extensive and intensive properties;

19. Chemical Property- the ability of a substance to combine with or change into one or more substances • Na + Cl = NaCl (Salt)

20. Examples of Chemical Properties • Ability to rust • Formation of precipitate • Reacts with water, oxygen, acids, bases, or other substances • Flammability

21. Physical Properties of Matter • Physical property- characteristic that can be observed or measured without changing the sample’s composition • Qualitative!!

22. Examples of Physical Properties • Density • Color • Odor • Taste • Hardness • Melting Point • Boiling Point

23. Extensive Properties • Dependent upon amount of substance present • Mass, Length, Volume • It changes if you take away some of the substance.

24. Intensive properties • Independent of amount of substance present • Examples: Density, color, odor, boiling point. • Intensive properties Don’t change and can be used to identify the substance.

25. Miners often got Pyrite (fool’s gold) and real gold mixed up. But Density could be used to correct the error. • The density of gold is 19.3 g/mL and the density of pyrite is 5 g/mL Pyrite – fools gold Gold

26. Properties of Copper

27. Both are copper

28. Properties of Matter Chemical Properties Physical Properties Reactions in the presence of Water, Air, Acid, Base What happens when heated Extensive Properties Depends on the amount _______________ Mass, Volume, Length, Shape Intensive Properties Do NOT depend on the amount ________________ E.G Color, Taste, Melting/Boiling Point, Luster, Hardness http://www.roomd113.com/TAKS%20PP/matterclass_pres.ppt

29. Evidence of a Chemical Reaction • The observation that the product has different properties than the reactant(s). • Clues: • If something can burn • Production of energy, such as light, heat, or sound • Formation of a gas • Formation of a solid – called a precipitate • Change in odor • Change in color

30. MATTER yes no Can it be physically separated? MIXTURE PURE SUBSTANCE yes no yes no Is the composition uniform? Can it be chemically decomposed? Homogeneous Mixture Heterogeneous Mixture Compound Element Suspensions Colloids Solutions

31. Thursday • Chromatography lab • Methods of separation

32. 3.3 Mixtures of Matter TEKS • 2.(E) plan and implement investigative procedures, including asking questions, formulating testable hypotheses, and selecting equipment and technology • 4. (D) Classify matter as pure substances or mixtures through investigation of their properties.

33. 3.3 Mixtures of Matter • Mixture- combination of two or more pure substances in which each retains its individual chemical properties.

34. Examples of Mixtures • Sand and water • Salt and Water • If the substances do not react and can be separated by physical means, it is a mixture.

35. Types of Mixtures • Heterogeneous Mixture- does not blend smoothly and individual substances remain distinct. (can see the different parts) • Ex: salad, pizza

36. Homogeneous Mixture- constant composition throughout (looks the same throughout) • Also known as solutions • Ex: Koolaid, air, sea water, sodas, vinegar, steel

37. Types of Solution Systems

38. Colloid • A heterogeneous mixture with particles larger than those in a solution • Example : milk

39. Suspension • A heterogeneous mixture whose particles settle out over time and can be separated from the mixture by filtration • Example lead paint

40. Separating Mixtures • Because mixtures are physically combined, the processes are used to separate themare based on the difference in physical properties of the substances. • 4 methods for separation

41. Filtration • Uses a porous barrier to separate a solid from a liquid

42. Distillation • Based on differences in boiling points of the substances • Heat mixture until substance with lowest boiling point boils to a vapor which is then condensed into a liquid

43. Crystallization • Results in formation of pure solid particles of a substance from a solution containing the dissolved substance

44. Chromatography • Separates the components of a mixture (called the mobile phase) on the basis of the tendency of each to travel or be drawn across the surface of another material (called the stationary phase)

45. Friday 10-bottle lab and finish notes on methods of separation

46. States of matter

47. 3.4 Elements and Compounds TEKS • 4. (D) Classify matter as pure substances or mixtures through investigation of their properties.

48. 3.4 Elements and Compounds • Element- Pure substance that can not be separated into simpler substances by physical or chemical means • Examples: Copper, Oxygen, Iodine

49. Each element has a unique chemical name and symbol. • The first letter is always capitalized, the rest are lowercase. • Ex: • Oxygen O • Carbon C • Iron Fe

50. Periodic Table • In 1869 Dmitri Mendeleev devised a chart which organized all of the known elements into rows and columns based on their similarities and masses.