1. M.I.T. C.P. CHEMISTRY Introduction to Measurement

2. Science is based on measurements.

3. All measurements have: Units

4. Length Foot = Length of Hercules’s Foot Mile = 1000 Soldiers’ Paces

6. 1790

7. SI Units QuantityBase UnitSymbol LengthMeterm MassKilogramkg VolumeLiterl TemperatureKelvinK TimeSeconds

8. Meter 1 Meter Light travels in a vacuum during 1/299,792,458 of a second

9. Kilogram

10. 2.5 grams 5.0 grams

11. Liter 1 Liter Volume occupied by 1 kilogram of H 2 O

12. All measurements have: Magnitude Units

13. Metric Prefixes

14. Powers of Ten

17. Very Large Measurements k (kilo) means “one thousand of” M (mega) means “one million of” G (giga) means “one billion of”

18. Very Small Measurements c (centi) means “a hundredth of” m (milli) means “a thousandth of” n (nano) means “a billionth of”

19. What is a “Nanometer”?

20. What is “Nanotechnology”?

21. Ceramic “Nano” Pores

22. How Small Am I? Bacterium Red Blood Cell Carbon Buckyball DNA Molecule Strand of Human Hair

23. Strand of Human Hair60,000 nanometers Bacterium10,000 nanometers Red Blood Cell7,000 nanometers DNA Molecule2 nanometers Carbon Buckyball (C60)1 nanometer

24. How Many Nanometers?

25. Lab: Measurements That Make ¢!

26. Lab: Laboratory Procedures

27. Density

28. Lab: Interactive DensityInteractive

29. Scientific Notation Scientific notation is used to express very large or small numbers. 10,300,000,000,000,000,000,000 carbon atoms A carbon atom’s mass = 0.000,000,000,000,000,000,000,020 grams

30. Scientific notation consists of a coefficient multiplied by 10 raised to an exponent. 10,300,000,000,000,000,000,000 = 1.03 x 10^22 = 1.03 E22 0.000,000,000,000,000,000,000,020 = 2.0 x 10^-23 = 2.0 E-23

31. All measurements have: Magnitude Units Uncertainty

32. Accuracy & Precision AccuratePrecise Accuracy refers to the closeness of measurements to the correct or accepted value of the quantity measured. Precision refers to the closeness of a set of measurements of the same quantity made in the same way.

33. Percent Error Observed Value-Accepted Value/Accepted Value x 100%

34. Sample Problem You complete a lab and your product has a mass of 90 grams. You should have made 130 grams. What is your % error? Step 1: Step 2: Step 3: Observed – Accepted (Absolute Value)40 Error/Accepted0.308 Answer X 100%30.8%

35. Lab: Accuracy & Precision

37. Significant Figures

39. The numbers 1,2,3,4,5,6,7,8,9 are always significant! Rules for “0” Rule #1: Zeros between numbers are significant! 5063 Significant Figures 100504 Significant Figures

40. Rule #2: Zeros to the right of a number are NOT significant unless the are to the left of a decimal point! 48303 Significant Figures 4830.4 Significant Figures

41. Rule #3: Zeros to the right of a number & to the right of a decimal point are significant! 8.02 Significant Figures 16.404 Significant Figures

42. Rule #4: Zeros by themselves to the left or right of a decimal point are NOT significant! 0.061 Significant Figure 0.0081 Significant Figure

43. Math with Significant Figures Multiply or divide as you normally would! 2,000.45 X 3,200 =641440 Since 3,200 has only 2 “Sig Figs” 640,000 Your answer can only have as many “Sig Fig’s” as the number with the fewest significant figures!

44. Lab: Pipette Calibration

45. Dimensional Analysis Factor Label Method Unit Factor Method

46. How many seconds are there in a day? Step 1:What units do I know and I need in the answer? I’m starting with DAY and ending in SECONDS. Step 2:Choose CONVERSION FACTOR(S) that get rid of your starting unit and end with you desired unit.

47. 1 Day24 Hours 1 Day 60 Min.60 Seconds XX 1 Hour X 1 Min 1 X 24 X 60 X 60 = 86,400

48. If you are going 50 mph, how many feet/second are you traveling? Step 1:What units do I know and I need in the answer? I’m stating with MILES/HOUR and ending with FEET/SECOND. Step 2:Choose CONVERSION FACTOR(S) that get rid of your starting unit and end with you desired unit. There are 5280 feet in a mile!

49. If you are going 50 mph, how many feet/second are you traveling?

50. Your car's gas tank holds 18.6 gallons and is one quarter full. Your car gets 16 miles/gal. How far can you drive without running out of gas?

51. Your car's gas tank holds 18.6 gallons and is one quarter full. Your car gets 16 miles/gal. How far can you drive without running out of gas?

52. Power of the Graph! ChartGraph Organizes Data ☺ ☺ Displays Data ☺ ☺ Predicts Data ☺

53. Lab: Graph This!

56. Proportional Relationships Direct ProportionIndirect Proportion

57. Lab: It’s All in the Graph!

58. Unit Review Game Rags-to-Riches