1. Matter And Measurement Chapter 1 Introduction: Matter and Measurement John D. Bookstaver St. Charles Community College St. Peters, MO  2006, Prentice Hall Chemistry, The Central Science, 10th edition Theodore L. Brown; H. Eugene LeMay, Jr.; and Bruce E. Bursten

2. Matter And Measurement Chemistry: The study of matter and the changes it undergoes.

3. Matter And Measurement Scientific Method: A systematic approach to solving problems.

4. Matter And Measurement Hypothesis : a tentative explanation, based on experiments. Scientific law: a verbal statement or a mathematical equation that summarizes observations and experiments. Laws describe the behavior of matter. Theory: an explanation of the general causes of certain phenomena with considerable evidence or facts to support it. Theories can never be proven to be absolutely correct!

5. Matter And Measurement Copyright©2000 by Houghton Mifflin Company. All rights reserved. 5 Law v. Theory A law summarizes what happens;A law summarizes what happens; A theory (model) is an attempt to explain why it happens.A theory (model) is an attempt to explain why it happens.

6. Matter And Measurement Matter: Anything that has mass and takes up space.

7. Matter And Measurement Matter Atoms are the building blocks of matter.

8. Matter And Measurement Matter Atoms are the building blocks of matter. Each element is made of the same kind of atom.

9. Matter And Measurement Matter Atoms are the building blocks of matter. Each element is made of the same kind of atom. A compound is made of two or more different kinds of elements.

10. Matter And Measurement Pure Substances and Mixtures

11. Matter And Measurement States of Matter

12. Matter And Measurement Pure Substances and Mixtures If matter is not uniform throughout, then it is a heterogeneous mixture. If matter is uniform throughout, it is homogeneous. If homogeneous matter can be separated by physical means, then the matter is a mixture. If homogeneous matter cannot be separated by physical means, then the matter is a pure substance. If a pure substance can be decomposed into something else, then the substance is a compound.

13. Matter And Measurement Elements If a pure substance cannot be decomposed into something else, then the substance is an element. There are 114 elements known. Each element is given a unique chemical symbol (one or two letters). Elements are building blocks of matter. The earth’s crust consists of 5 main elements. (O, Si, Al, Fe, Ca) The human body consists mostly of 3 main elements. (O, C, H)

14. Matter And Measurement Elements

15. Matter And Measurement Classification of Matter

16. Matter And Measurement Classification of Matter

17. Matter And Measurement Classification of Matter

18. Matter And Measurement Classification of Matter

19. Matter And Measurement Classification of Matter

20. Matter And Measurement Classification of Matter

21. Matter And Measurement Classification of Matter

22. Matter And Measurement Classification of Matter

23. Matter And Measurement Classification of Matter

24. Matter And Measurement Classification of Matter

25. Matter And Measurement Mixtures and Compounds

26. Matter And Measurement Properties and Changes of Matter

27. Matter And Measurement Properties of Matter Physical Properties: □Can be observed without changing a substance into another substance. Boiling point, density, mass, volume, etc. Chemical Properties: □Can only be observed when a substance is changed into another substance. Flammability, corrosiveness, reactivity with acid, etc.

28. Matter And Measurement Properties of Matter Intensive Properties: □Independent of the amount of the substance that is present. Density, boiling point, color, etc. Extensive Properties: □Dependent upon the amount of the substance present. Mass, volume, energy, etc.

29. Matter And Measurement Changes of Matter Physical Changes: □Changes in matter that do not change the composition of a substance. Changes of state, temperature, volume, etc. Chemical Changes: □Changes that result in new substances. Combustion, oxidation, decomposition, etc.

30. Matter And Measurement Chemical Reactions In the course of a chemical reaction, the reacting substances are converted to new substances.

31. Matter And Measurement Chemical Reactions

32. Matter And Measurement Compounds Compounds can be broken down into more elemental particles.

33. Matter And Measurement Electrolysis of Water

34. Matter And Measurement Separation of Mixtures

35. Matter And Measurement Distillation: Separates homogeneous mixture on the basis of differences in boiling point.

36. Matter And Measurement Distillation

37. Matter And Measurement Filtration: Separates solid substances from liquids and solutions.

38. Matter And Measurement Chromatography: Separates substances on the basis of differences in solubility in a solvent.

39. Matter And Measurement Units of Measurement

40. Matter And Measurement SI Units There are two types of units: –fundamental (or base) units; –derived units. There are 7 base units in the SI system.

41. Matter And Measurement SI Units Système International d’Unités Uses a different base unit for each quantity

42. Matter And Measurement Metric System Prefixes convert the base units into units that are appropriate for the item being measured.

43. Matter And Measurement Volume The units for volume are given by (units of length) 3. –SI unit for volume is 1 m 3. We usually use 1 mL = 1 cm 3. Other volume units: –1 L = 1 dm 3 = 1000 cm 3 = 1000 mL.

44. Matter And Measurement Uncertainty in Measurements Different measuring devices have different uses and different degrees of accuracy.

45. Matter And Measurement Temperature: A measure of the average kinetic energy of the particles in a sample.

46. Matter And Measurement Temperature In scientific measurements, the Celsius and Kelvin scales are most often used. The Celsius scale is based on the properties of water. □0  C is the freezing point of water. □100  C is the boiling point of water.

47. Matter And Measurement Temperature The Kelvin is the SI unit of temperature. It is based on the properties of gases. There are no negative Kelvin temperatures. K =  C + 273.15

48. Matter And Measurement Temperature The Fahrenheit scale is not used in scientific measurements.  F = 9/5(  C) + 32  C = 5/9(  F − 32)

49. Matter And Measurement Examples: 1.What is 35ºC in Kelvin? In ºF? 2.What is 183 K in ºC? In ºF?

50. Matter And Measurement Density: Physical property of a substance d=d= mVmV

51. Matter And Measurement Examples: 1.An object with a mass of 17.95 g occupies a volume of 11.8 mL. What is its density? 2.A sample with a density of 3.75 g cm -3 occupies a volume of 10.44 cm 3. What is the mass of the sample? 3.A graduated cylinder is filled with 15.0 cm 3 of water. An object with a mass of 29.66 g causes the total volume to increase to 23.4 mL. What is the density of the sample?

52. Matter And Measurement Uncertainty in Measurement

53. Matter And Measurement Significant Figures The term significant figures refers to digits that were measured. When rounding calculated numbers, we pay attention to significant figures so we do not overstate the accuracy of our answers.

54. Matter And Measurement Uncertainty in Measurement All scientific measures are subject to error. These errors are reflected in the number of figures reported for the measurement. These errors are also reflected in the observation that two successive measures of the same quantity are different. Precision and Accuracy Measurements that are close to the “correct” value are accurate. Measurements that are close to each other are precise.

55. Matter And Measurement ACCURACY DEALS WITH THE EXACTESNESS OF THE MEASUREMENT, HOW CLOSE IT IS TO THE, TRUE, ACCEPTED OR STANDARD VALUE PRECISSION DEALS WITH REPRODUCIBILITY OF A MEASUREMENT. IF SEVERAL MEASUREMENTS GIVE A SIMILAR RESULT IT IS SAID THAT THE MEASUREMENT IS PRECISE

56. Matter And Measurement Accuracy versus Precision Accuracy refers to the proximity of a measurement to the true value of a quantity. Precision refers to the proximity of several measurements to each other.

57. Matter And Measurement Copyright©2000 by Houghton Mifflin Company. All rights reserved. 57 Dimensional Analysis Proper use of “unit factors” leads to proper units in your answer.

58. Matter And Measurement Significant Figures The number of digits reported in a measurement reflect the accuracy of the measurement and the precision of the measuring device. All the figures known with certainty plus one extra figure (estimated digit) are called significant figures. In any calculation, the results are reported to the fewest significant figures (for multiplication and division) or fewest decimal places (addition and subtraction).

59. Matter And Measurement Significant Figures 1.All nonzero digits are significant. 2.Zeroes between two significant figures are themselves significant. 3.Zeroes at the beginning of a number are never significant. 4.Zeroes at the end of a number are significant if a decimal point is written in the number or if they are to the right of a decimal point.

60. Matter And Measurement 0.0030 has 2 sf 400. Has 3 sf 700.00 has 5 sf

61. Matter And Measurement Scientific Notation Numbers written in scientific notation include a numeral with one digit before the decimal point, multiplied by some power of ten (6.022 x 10 23 ) In scientific notation, all digits are significant. You should be able to convert from non-scientific notation to scientific and vice-versa.

62. Matter And Measurement Copyright©2000 by Houghton Mifflin Company. All rights reserved. 62 Rules for Significant Figures in Mathematical Operations Addition and Subtraction: # sig figs in the result equals the number of decimal places in the least precise measurement.Addition and Subtraction: # sig figs in the result equals the number of decimal places in the least precise measurement. 6.8 + 11.934 = 22.4896  22.5 (3 sig figs)

63. Matter And Measurement Examples: How many significant figures are in each of the following? 1.52300 m 2.0.000487 kg 3.29.0400 s 4.507 people 5.230,050 cm 6.45.600 A

64. Matter And Measurement Dimensional Analysis Method of calculation utilizing a knowledge of units. Given units can be multiplied or divided to give the desired units. Conversion factors are used to manipulate units: Desired unit = given unit  (conversion factor) The conversion factors are simple ratios:

65. Matter And Measurement Using Two or More Conversion Factors Example to convert length in meters to length in inches:

66. Matter And Measurement Using Two or More Conversion Factors In dimensional analysis always ask three questions: What data are we given? What quantity do we need? What conversion factors are available to take us from what we are given to what we need?

67. Matter And Measurement Examples: Convert the following: 1.240 000 000 nm to cm. 2.0.00657 dm 3 to cm 3. 3.25.7 years to s. 4.4.98 feet to mm.