Unit 1. Matter and Change

1. Unit 1. Matter and Change

2. Do Now: • What are the parts of the scientific method and explain each part?

3. Objective • Identify the common steps of scientific methods • Identify types of variables • Describe the difference between a theory and a scientific law • Identify the characteristics of a substance • Distinguish between physical and chemical properties • Differentiate among the physical states of matter

4. Objectives Continued • Define physical and chemical changes and list common changes • Apply the law of conservation of mass to chemical reactions • Activities: • Q&A • Solve problems • Exit Ticket

5. Scientific Method (p12) • Systematic approach used in scientific study • Method for scientists to verify the work of others

6. Steps of Scientific Method • Observation • Hypothesis • Experiments • Conclusion • Theory/ Scientific Law

7. Observation • Act of gathering information • Qualitative Data- color, shape, odor other physical characteristics • Quantitative Data – some type of measurement. It is numerical. Ex. Height, weight, how fast, how slow etc.

8. Hypothesis • Tentative explanation for what has been observed.

9. Experiment • Set of controlled observations used to test the hypothesis • Must carefully plan and set up one or more laboratory experiments in order to change and test one variable at a time. • Independent Variable – Variable that you plan to change. ( what you can control) • Dependent Variable – variable that changes based on the independent variable

10. Conclusion • Judgment based on the information obtained

11. Ch. 3 - Matter I. Kinetic Molecular Theory States of Matter

12. A. Kinetic Molecular Theory • KMT • Particles of matter are always in motion. • The kinetic energy (speed) of these particles increases as temperature increases.

13. Three States of Matter • Solids • very low KE - particles vibrate but can’t move around • fixed shape • fixed volume

14. Three States of Matter • Liquids • low KE - particles can move around but are still close together • variable shape • fixed volume

15. Three States of Matter • Gases • high KE - particles can separate and move throughout container • variable shape • variable volume • Vapor- Gaseous state of a substance that is a solid or liquid at room temperature.

16. Matter and its Properties • It’s Classified!

17. Physical vs. Chemical • Physical Property • can be observed without changing the identity of the substance • Extensive or intensive properties • Chemical Property • describes the ability of a substance to undergo changes in identity

18. Extensive vs. Intensive • Extensive Property • depends on the amount of matter present • ex,.- • Intensive Property • depends on the identity of substance, not the amount • Ex.-

19. Extensive vs. Intensive • Extensive Property • depends on the amount of matter present • ex,.- Volume, mass, Energy • Intensive Property • depends on the identity of substance, not the amount • Ex.- melting point, boiling point, conduct electricity or heat • WHAT ABOUT DENSITY??

20. A. Extensive vs. Intensive • Examples: • boiling point • volume • mass • density • conductivity

21. A. Extensive vs. Intensive • Examples: • boiling point…… intensive • Volume …. extensive • Mass ….. extensive • Density ….. intensive • Conductivity ….. intensive

22. Physical vs. Chemical • Physical Change • changes the form of a substance without changing its identity • properties remain the same • Chemical Change • changes the identity of a substance • products have different properties

23. Signs of a Chemical • change in color or odor • formation of a gas • formation of a precipitate (solid) • change in light or heat

24. B. Physical vs. Chemical physical chemical physical physical chemical • Examples: • melting point • flammable • density • magnetic • tarnishes in air

25. B. Physical vs. Chemical physical chemical physical physical chemical • Examples: • melting point • flammable • density • magnetic • tarnishes in air

26. B. Physical vs. Chemical • Examples: • rusting iron • dissolving in water • burning a log • melting ice • grinding spices

27. B. Physical vs. Chemical chemical physical chemical physical physical • Examples: • rusting iron • dissolving in water • burning a log • melting ice • grinding spices

28. Law of Conservation of Mass • Mass is neither created nor destroyed during a chemical reaction. It is conserved • In a chemical reaction, the mass of the reactants must equal the mass of the products

29. Law of Conservation of Mass Pg. 78 #7 A student carefully placed 15.6 g of sodium in a reactor supplied with an exess quantity of chlorine gas. When the reaction was complete, the student obtained 39.7f of sodium chloride. Calculate how many grams of chlorine gas reacted. How many grams of sodium reacted?

30. Law of Conservation of Mass Pg. 78 #7 A student carefully placed 15.6 g of sodium in a reactor supplied with an exess quantity of chlorine gas. When the reaction was complete, the student obtained 39.7f of sodium chloride. Calculate how many grams of chlorine gas reacted. How many grams of sodium reacted? 24.1 g of chlorine gas, 15.6 of sodium

31. Law of Conservation of Mass Pg. 78 #7 A student carefully placed 15.6 g of sodium in a reactor supplied with an exess quantity of chlorine gas. When the reaction was complete, the student obtained 39.7f of sodium chloride. Calculate how many grams of chlorine gas reacted. How many grams of sodium reacted? 24.1 g of chlorine gas, 15.6 of sodium

32. HW • Pg 79 (10 and 13 only)

33. Do Now: • DO NOW: • What is a solution? • Describe the difference between a heterogeneous and homogenous mixture • Calculate % by Mass

34. Objective: • SWBAT: • Contrast Mixtures and substances • Classify mixtures as homogeneous or heterogeneous • List and describe several techniques used to separate mixtures. • Distinguish between elements and compounds • Activities • Q&A • Solve problems • Exit Ticket

35. Objective: • Activities:

36. MIXTURE PURE SUBSTANCE yes no yes no Is the composition uniform? Can it be chemically decomposed? Colloids Suspensions A. Matter Flowchart MATTER yes no Can it be physically separated? Homogeneous Mixture (solution) Heterogeneous Mixture Compound Element

37. A. Matter Flowchart • Examples: • graphite • pepper • sugar (sucrose) • paint • soda

38. A. Matter Flowchart element hetero. mixture compound hetero. mixture solution • Examples: • graphite • pepper • sugar (sucrose) • paint • soda

39. Pure Substances • Element • composed of identical atoms • EX: copper wire, aluminum foil

40. Pure Substances • Compound • composed of 2 or more elements in a fixed ratio • properties differ from those of individual elements • EX: table salt (NaCl)

41. Pure Substances • Law of Definite Composition • A given compound always contains the same, fixed ratio of elements. • Law of Multiple Proportions • Elements can combine in different ratios to form different compounds.

42. Pure Substances • For example… Two different compounds, each has a definite composition.

43. Elements Listed on the Periodic Table Cannot be broken down into unique components Na, Cl, Al, O2, S8 Compounds Made of elements that are chemically joined Can be broken down NaCl, H2O, AlCl3, H2SO4 Pure Substances(constant composition)

44. Diatomic Elements • Hydrogen • Nitrogen • Oxygen • Fluorine • Chlorine • Bromine • Iodine • There are 7 diatomic elements • These atoms are never alone, if they are the pair up with the same atom

45. C. Mixtures • Variable combination of 2 or more pure substances. Heterogeneous Homogeneous

46. Tyndall Effect C. Mixtures • Solution • homogeneous • very small particles • no Tyndall effect

47. C. Mixtures • Colloid • heterogeneous • medium-sized particles • Tyndall effect • particles don’t settle • EX: milk

48. C. Mixtures • Suspension • heterogeneous • large particles • Tyndall effect • particles settle • EX: fresh-squeezed lemonade

49. Homogeneous – Solutions evenly distributed Heterogeneous not evenly distributed Mixtures(variable composition)

50. Tea – Homogeneous Mixture