1. Chapter(2,3): Science and Measurements Copyright © 2014 John Wiley & Sons, Inc. All rights reserved.

2. © 2014 John Wiley & Sons, Inc. All rights reserved.

3. 1.1 Scientific Method Objectives Explain the terms: law, hypothesis, experiment, and theory © 2014 John Wiley & Sons, Inc. All rights reserved.

4. Scientific knowledge deeply impacts our lives DNA fingerprinting Pesticides Cleaner fuels Medical discoveries Therapeutic drugs MRI and CT scanners 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

5. Science is broken into various disciplines Chemistry involves the study of matter and its changes Knowledge important in many other disciplines like biology, health sciences, and geology 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

6. For all science, information is gathered and interpreted using the scientific method Making observations is very important English Physicist, Sir Isaac Newton, formulated the law of gravity after observing an apple falling from a tree 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

7. 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved. Law

8. Laws describe things that are consistently and reproducibly observed Predict what might happen in the future Does not describe WHY things happen 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

9. Hypotheses are made based on observations Educated guess Tentative explanation of what was seen Clinicians make hypotheses when treating patients. 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

10. Clinicians make hypotheses when treating patients prior to ordering medical tests A series of experiments are used to test a hypothesis May support the hypothesis or cause for the hypothesis to be revised 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

11. If experiments continually support a hypothesis, it may become a theory An experimentally tested explanation of an observed behavior Must predict results of future experiments Must explain future observations 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

12. 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved. Law

13. As science and technology changes and improves, theories and hypotheses may have to change 1.1 Scientific Method © 2014 John Wiley & Sons, Inc. All rights reserved.

14. Which of the following terms describes things that are consistently and reproducibly observed? a. Law b. Theory c. Experiment d. Hypothesis © 2014 John Wiley & Sons, Inc. All rights reserved.

16. 1.2 Matter and Energy Objectives Define matter and energy Describe three states of matter and two forms of energy Describe physical properties and physical change Be able to provide examples of each © 2014 John Wiley & Sons, Inc. All rights reserved.

17. 1.2 Matter and Energy Matter described in terms of physical properties characteristics that can be determined without changing what it is made of (chemical composition) Melting and boiling points Color Physical State Odor © 2014 John Wiley & Sons, Inc. All rights reserved.

18. 1.2 Matter and Energy Matter is generally found in one of three physical states or phases 1.Solid Have fixed shapes and volumes 2.Liquid Have variable shapes and fixed volumes 3.Gas Have variable shapes and volumes © 2014 John Wiley & Sons, Inc. All rights reserved.

19. 1.2 Matter and Energy What causes different phases? Interactions between particles (atoms, molecules, ions) © 2014 John Wiley & Sons, Inc. All rights reserved.

20. Which of the following represents a physical change a. Iron rusting b. Milk souring c. Slicing a tomato d. Exploding of nitroglycerin © 2014 John Wiley & Sons, Inc. All rights reserved.

21. 1.2 Matter and Energy Work has been done any time matter is changed Involves energy ability to do work and to transfer heat © 2014 John Wiley & Sons, Inc. All rights reserved.

22. 1.2 Matter and Energy Energy is found in two forms 1.Potential energy Stored energy For example: water behind a dam 2.Kinetic energy Energy of motion For example: water flowing through the dam © 2014 John Wiley & Sons, Inc. All rights reserved.

23. 1.2 Matter and Energy Along with particle interaction; heat plays a role in states of matter As temperature increases, kinetic energy increases For example ice has less kinetic energy than liquid water © 2014 John Wiley & Sons, Inc. All rights reserved.

24. Which of the following is an example of potential energy? a. Car rolling down a hill b. Climber ascending down a mountain c. Clock hands rotating d. Hammer sitting a top a latter © 2014 John Wiley & Sons, Inc. All rights reserved.

25. 1.2 Matter and Energy Heat of fusion is the energy required to melt a solid Heat of vaporization is the energy required to go from the liquid to gas phase (vaporize) © 2014 John Wiley & Sons, Inc. All rights reserved.

26. 1.2 Matter and Energy Some substances can jump directly from solid to gas phases under the correct conditions Sublimation The reverse, going from gas directly to a solid is called deposition © 2014 John Wiley & Sons, Inc. All rights reserved.

27. In which state of matter do molecules have the least amount of interactions with one another? a. Solid b. Liquid c. Gas d. Suspension © 2014 John Wiley & Sons, Inc. All rights reserved.

28. What statement is true about liquid water turning to steam? a. The particles have more interactions b. The water has sublimed c. Kinetic energy is increasing d. A chemical change has occurred © 2014 John Wiley & Sons, Inc. All rights reserved.

30. 1.3 Units of Measurement Objectives Identify metric, English, and SI units © 2014 John Wiley & Sons, Inc. All rights reserved.

31. 1.3 Units of Measurement Looking at your watch, baking a cake or taking cough syrup all require measurements Measurements have two parts Number and a unit 500 milligrams Unit is a quantity that is used as a standard of measurement (time, length, volume, etc.) © 2014 John Wiley & Sons, Inc. All rights reserved.

32. 1.3 Units of Measurement Metric system is used most often worldwide Use the English units in the United States SI units are also used at times International system of units related to the metric system © 2014 John Wiley & Sons, Inc. All rights reserved.

33. 1.3 Units of Measurement Mass is the measure of the amount of matter in a sample Most often measured in kilogram (kg) and gram (g) 1 kg = 1000 g = 2.205 lb © 2014 John Wiley & Sons, Inc. All rights reserved.

34. 1.3 Units of Measurement © 2014 John Wiley & Sons, Inc. All rights reserved.

35. 1.3 Units of Measurement © 2014 John Wiley & Sons, Inc. All rights reserved.

36. 1.3 Units of Measurement Mass vs Weight Mass is the measure of the amount of matter in an object Weight is dependent upon the force of gravity Weight changes based on where the object is located A person weighing 150 lb on earth would weigh only 25 lb on the moon © 2014 John Wiley & Sons, Inc. All rights reserved.

37. 1.3 Units of Measurement © 2014 John Wiley & Sons, Inc. All rights reserved.

38. 1.3 Units of Measurement Unit of measure for energy is the calorie (cal) in metric and English systems One calorie is the amount of energy required to raise the temperature of 1 g of water by 1 °C. One food Calorie (Cal) = 1000 cal © 2014 John Wiley & Sons, Inc. All rights reserved.

40. 1.4 Scientific Notation, SI and Metric Prefixes Objectives Express values in scientific notation © 2014 John Wiley & Sons, Inc. All rights reserved.

41. 1.4 Scientific Notation, SI and Metric Prefixes Measurements are taken both small and large blood cell 0.000 0075 m earth to sun 150 000 000 000 m To eliminate so many zeros, very large (or very small) numbers are written in scientific notation exponential notation Example: 0.000 0060 m is 6.0 x 10 -6 m © 2014 John Wiley & Sons, Inc. All rights reserved.

42. 1.4 Scientific Notation, SI and Metric Prefixes Values expressed in scientific notation are written as a number between 1 and 10 multiplied by a power of 10 1234 in scientific notation is 1.234 x 10 3 The superscripted number to the right of the 10 is called an exponent 1.234 x 10 3 © 2014 John Wiley & Sons, Inc. All rights reserved.

43. 1.4 Scientific Notation, SI and Metric Prefixes For numbers larger than 10, shift the decimal point to the left until you get a number between 1 and 10 505000 = 5.05 x 10 5, positive exponent For numbers smaller than 10, shift the decimal point to the right. The exponent will be negative 0.000000505 = 5.05 x 10 -7 © 2014 John Wiley & Sons, Inc. All rights reserved.

44. Which represents 0.000305 in correct scientific notation? a. 3.05 x 10 4 b. 0.305 x 10 -3 c. 3.05 x 10 -4 d. 30.5 x 10 -5 © 2014 John Wiley & Sons, Inc. All rights reserved.

45. 1.4 Scientific Notation, SI and Metric Prefixes To express large and small numbers in the SI and metric systems, prefixes are used prefixes create new units and indicate how the new relates to the original For instance milliliter indicates litter has been multiplied by 10 -3 (or 0.001) Therefore 10 -3 L = 1 mL or 1 L = 1000 mL © 2014 John Wiley & Sons, Inc. All rights reserved.

46. 1.4 Scientific Notation, SI and Metric Prefixes © 2014 John Wiley & Sons, Inc. All rights reserved. 1m or 1g

47. 1.4 Scientific Notation, SI and Metric Prefixes The distance from New York to California is approximately 4,800,000 meters. How many kilometers is this? 4,800,000 m x 1 km = 10 3 m 4,800 km / / © 2014 John Wiley & Sons, Inc. All rights reserved.

48. 1.4 Scientific Notation, SI and Metric Prefixes A bottle holds 0.5 L water. Express this volume by adding an appropriate prefix to “liter.” Can also be written as: 0.5 L x 1 dL = 10 -1 L 5 dL / / 0.5 L x 10 dL = 1 L 5 dL / / © 2014 John Wiley & Sons, Inc. All rights reserved. 0.5 L

49. © 2014 John Wiley & Sons, Inc. All rights reserved.

50. 1.5 Measurements and Significant Figures Objectives Describe the difference between the terms accurate and precise Use the correct number of significant figures in the results of calculations involving measurements © 2014 John Wiley & Sons, Inc. All rights reserved.

51. 1.5 Measurements and Significant Figures When determining the validity of measurements, three factors need to be considered 1.Accuracy 2.Precision 3.Significant Figures © 2014 John Wiley & Sons, Inc. All rights reserved.

52. 1.5 Measurements and Significant Figures Accuracy is related to how close a measured value is to a true value Precision is a measure of reproducibility © 2014 John Wiley & Sons, Inc. All rights reserved.

53. 1.5 Measurements and Significant Figures Quality of equipment is one factor used in determining how precise and accurate a measurement is © 2014 John Wiley & Sons, Inc. All rights reserved.

54. 1.5 Measurements and Significant Figures Significant Figures digits in a measurement that are reproducible when the measurement is repeated. Plus the first uncertain digit You measure the mass of a quarter on a balance that produces readings with 0.1 g The mass reads. The 7 is uncertain 5.7 g ±0.1 0.1 uncertainty( precision) © 2014 John Wiley & Sons, Inc. All rights reserved.

55. 1.5 Measurements and Significant Figures Significant Figures pertain to measurements because there is always some degree of error Exact numbers have unlimited number of significant figures Obtained by exact count For instance, there are 7 patients in the waiting room © 2014 John Wiley & Sons, Inc. All rights reserved.

56. 1.5 Measurements and Significant Figures © 2014 John Wiley & Sons, Inc. All rights reserved. = 6×10 -4

57. 1.5 Measurements and Significant Figures Calculations with measured values should never change the degree of uncertainty in a value Multiplication and Division The answer should have the same number of significant figures as the quantity with the fewest © 2014 John Wiley & Sons, Inc. All rights reserved.

58. 1.5 Measurements and Significant Figures Addition and Subtraction The answer should have the same number of decimal places as the quantity with the fewest decimal places © 2014 John Wiley & Sons, Inc. All rights reserved.

59. 1.5 Measurements and Significant Figures When dropping digits of an answer to report the value with the correct number of significant figures, rounding must occur If the first digit dropped is 0 to 4, the last reported digit does not change If the first digit dropped is 5 to 9, the last reported digit is increased by 1 © 2014 John Wiley & Sons, Inc. All rights reserved.

60. Examples of the Use of Significant Figures SUM / SUBSTRACT 0.005 45.01 100.0 145.015  145.0 -21.304 5.05 -16.254  -16.25 MULTIPL / DIVISION 105.500 x 2.00 = 211 42.120 ÷ 3.000 =14.04

61. What is the answer to 620 x 5.125 with the correct significant figures? a. 3177.5 b. 318 c. 3180 d. 3200 © 2014 John Wiley & Sons, Inc. All rights reserved.

63. 1.6 Conversion Factors and the Factor Label Method Objectives Identify conversion factors and use them to convert from one unit to another © 2014 John Wiley & Sons, Inc. All rights reserved.

64. 1.6 Conversion Factors and the Factor Label Method Unit conversions allow us to convert the value of a measurement from one unit into another For instance 12 inches is 1 foot More complex conversions can be performed using the factor label method a systematic approach using conversion factors © 2014 John Wiley & Sons, Inc. All rights reserved.

65. 1.6 Conversion Factors and the Factor Label Method How many eggs are in 2 dozen? 1 dozen = 12 eggs Conversion factor 2 dozen eggs x 12 eggs = 1 dozen 24 eggs / / Factor label method: multiply by the conversion factor © 2014 John Wiley & Sons, Inc. All rights reserved.

66. 1.6 Conversion Factors and the Factor Label Method A 185 lbs patient is prescribed a drug whose dosage is listed in terms of kilograms. Patient’s weight in kilograms? Conversion factor: 2.205 lb = 1 kg 185 lb x _1 kg_ 2.205 lb = 83.9 kg / / © 2014 John Wiley & Sons, Inc. All rights reserved.

67. 1.6 Conversion Factors and the Factor Label Method Sometimes unit conversions must be done in multiple steps Convert the average volume of blood pumped by one beat of your heart (0.070 L) from liters into cups. 0.070 L x _1 qt_ 0.946 L = 0.074 qt / / 0.074 qt x _4 cups_ 1 qt = 0.30 cups / / © 2014 John Wiley & Sons, Inc. All rights reserved.

68. 1.6 Conversion Factors and the Factor Label Method A child is prescribed 45mg amoxicillin every 12 hours. The available suspension contains 125mg per every 5.0mL. How many milliliters should be given? 45 mg amoxicillin x _ 5.0 mL _ 125 mg amoxicillin = 1.8 mL / / © 2014 John Wiley & Sons, Inc. All rights reserved.

69. You are instructed to give a patient 2.8 mL of medicine; however, you can only find a teaspoon. If 1 tsp = 5 mL, how much would you give the patient? a. 0.56 tspb. 1.8 tsp c. 7.8 tspd. 14 tsp © 2014 John Wiley & Sons, Inc. All rights reserved.

70. 1.6 Conversion Factors and the Factor Label Method Temperature conversions ° F = (1.8 x ° C) + 32 ° C = ° F -32 1.8 K = °C + 273.15 °C = K - 273.15 © 2014 John Wiley & Sons, Inc. All rights reserved.

71. 1.6 Conversion Factors and the Factor Label Method A European tourist comes into the emergency room stating that his 3 month old daughter is ill and has a fever of 38.9 °C. Should you be concerned? What is this temperature in °F? (normal: 97.7–99.5 °F) °F = (1.8 x 38.9 °C) + 32 = 102 °F © 2014 John Wiley & Sons, Inc. All rights reserved.

72. How many Kelvin is 235 °F? a. 386 b. 212 c. 455 d. 508 © 2014 John Wiley & Sons, Inc. All rights reserved.

74. 1.7 Density, Specific Gravity and Specific Heat Objectives Explain the terms density, specific gravity and specific heat © 2014 John Wiley & Sons, Inc. All rights reserved.

75. 1.7 Density, Specific Gravity and Specific Heat Density is the amount of mass contained in a given volume units usually expressed in g/cm 3 for solids g/mL for liquids g/L for gases Density = Mass Volume © 2014 John Wiley & Sons, Inc. All rights reserved.

76. 1.7 Density, Specific Gravity and Specific Heat © 2014 John Wiley & Sons, Inc. All rights reserved.

77. 1.7 Density, Specific Gravity and Specific Heat What is the mass (in grams) of a 15.0 mL saline solution that has a density of 1.05 g/mL? D = 1.05 g/mL= _____ 15.0 mL m V g g = 1.05 g/mL x 15.0 mL g = 15.8 g © 2014 John Wiley & Sons, Inc. All rights reserved.

78. 1.7 Density, Specific Gravity and Specific Heat Specific gravity relates the density of a substance to that of water Likely to vary with temperature because a change in temperature affects both the density of water and the substance Specific gravity = Density of substance Density of water © 2014 John Wiley & Sons, Inc. All rights reserved.

79. 1.7 Density, Specific Gravity and Specific Heat © 2014 John Wiley & Sons, Inc. All rights reserved. Hydrometer

80. 1.7 Density, Specific Gravity and Specific Heat Specific heat is the amount of heat energy required to raise the temperature of 1 gram of a substance 1 °C © 2014 John Wiley & Sons, Inc. All rights reserved.

81. 1.7 Density, Specific Gravity and Specific Heat 1.5 Kg of water is needed to boil pasta. How much energy is required to raise the temperature of the water from 22 °C to 100.0 °C? Specific heat of water = 1.00 cal/g °C Can be used as a conversion factor Make sure units match!! Heat Energy: Q = m  c s  ∆T 1500 g x _____ g °C 1.00 cal x 78 °C = 117000 = 120000 cal © 2014 John Wiley & Sons, Inc. All rights reserved. / / / /

82. Calculate the mass in grams of a 15.0 mL of saline solution that has a density of 1.05 g/mL? a. 0.0700 g b. 14.3 g c. 15.8 g d. 0.0158 g © 2014 John Wiley & Sons, Inc. All rights reserved.

84. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry Objectives Recognize the difference between general chemistry, organic chemistry and biochemistry © 2014 John Wiley & Sons, Inc. All rights reserved.

85. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry Chemistry is broken down into many sub- disciplines Three important ones are: 1.General chemistry study of the fundamental principles of chemistry 2.Organic chemistry study of the chemistry of carbon 3.Biochemistry study of the chemistry of living things © 2014 John Wiley & Sons, Inc. All rights reserved.

86. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry General chemistry Deals with wide range of subjects including atoms, chemical reactions and units of measure © 2014 John Wiley & Sons, Inc. All rights reserved.

87. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry Organic chemistry Organic compounds have a carbon based skeleton Ones presented later on are small molecules Organic compounds knowledge helps us understand biological compounds © 2014 John Wiley & Sons, Inc. All rights reserved.

88. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry © 2014 John Wiley & Sons, Inc. All rights reserved.

89. 1.8 Measurements in General Chemistry, Organic Chemistry, and Biochemistry Biochemistry chemistry Includes study of compounds like carbohydrates, proteins and DNA Includes topics ranging from what happens when food is digested to how genetic information is passed from one generation to the next © 2014 John Wiley & Sons, Inc. All rights reserved.