1. Table of Contents Measurement–A Common Language
Mathematics and Science
Graphs in Science
Safety in the Science Laboratory

2. A Standard Measurement System
- Measurement–A Common Language
A Standard Measurement System
Using SI as the standard system of measurement allows scientists to compare data and communicate with each other about their results. SI units are based on multiples of 10.

3. Length - Measurement–A Common Language
The basic unit of length in the SI system is the meter (m).

4. Mass - Measurement–A Common Language
The basic unit of mass in the SI system is the kilogram (kg).

5. Volume - Measurement–A Common Language
Volume is the amount of space an object takes up.

6. Density - Measurement–A Common Language
Because density is actually made up of two other measurements–mass and volume–an object’s density is expressed as a combination of two units.

7. Calculating Density - Measurement–A Common Language
Suppose that a metal object has a mass of 57 g and a volume of 21 cm3. Calculate its density.
Read and Understand
What information are you given?
Mass of metal object = 57 g
Volume of metal object = 21 cm3

8. Calculating Density - Measurement–A Common Language
Suppose that a metal object has a mass of 57 g and a volume of 21 cm3. Calculate its density.
Plan and Solve
What quantity are you trying to calculate?
The density of the metal object = __
What formula contains the given quantities and the unknown quantity?
Density = Mass/Volume
Perform the calculation.
Density = Mass/Volume = 57 g/21 cm3 = 2.7 g/cm3

9. Calculating Density - Measurement–A Common Language
Suppose that a metal object has a mass of 57 g and a volume of 21 cm3. Calculate its density.
Look Back and Check
Does your answer make sense?
The answer tells you that the metal object has a density of 2.7 g/cm3. The answer makes sense because it is the same as the density of a known metal–aluminum.

10. Calculating Density Practice Problem - Measurement–A Common Language
What is the density of a wood block with a volume of 125 cm3 and a mass of 57 g?
0.46 g/cm3

11. Calculating Density Practice Problem - Measurement–A Common Language
What is the density of a liquid with a mass of 45 g and a volume of 48 mL?
0.94 g/mL

12. Time - Measurement–A Common Language
The second (s) is the SI unit to measure time.

13. Temperature - Measurement–A Common Language
In addition to the Celsius scale, scientists sometime use another temperature scale, called the Kelvin scale. The kelvin (K) is the official SI unit for temperature.

14. Converting Between Units
- Measurement–A Common Language
Converting Between Units
Using the appropriate conversion factor, you can easily convert one unit of measurement to another.
This example shows how to convert 1.5 kilometers to meters.

15. Comparing and Contrasting
- Measurement–A Common Language
Comparing and Contrasting
As you read, compare and contrast different types of measurement by completing a table like the one below.
Characteristic
Length
Mass
Time
Temperature
Distance from one point to another
Definition
Amount of matter
Passing of events
Hotness or coldness
Degrees of Celsius or Kelvin
SI Unit
Meter (m)
Gram (g)
Second (s)
Measuring Tool
Metric ruler
Balance
Watch or clock
Thermometer

16. Click the PHSchool.com button for an activity about measurement.
- Measurement–A Common Language
More on Measurement
Click the PHSchool.com button for an activity about measurement.

17. End of Section: Measurement– A Common Language

18. Area - Mathematics and Science
The area of a surface is the amount of space it covers. To find the area, multiply its length by its width. Remember to multiply the units as well.
Area = Length x Width
Suppose an area measures 12.0 m by 11.0 m.
Area = 12.0 m x 11.0 m = 132 m2
Practice Problem
Calculate the area of room 4.0 m long and 3.0 m wide.
4.0 m x 3.0 m = 12 m2

19. Area - Mathematics and Science
The area of a surface is the amount of space it covers. To find the area, multiply its length by its width. Remember to multiply the units as well.
Area = Length x Width
Suppose an area measures 12.0 m by 11.0 m.
Area = 12.0 m x 11.0 m = 132 m2
Practice Problem
Calculate the area of a ticket stub 5.1 mm long and 2.62 mm wide.
5.1 mm x 2.62 mm = 13.4 mm2 (13, to the correct significant figure)

20. Accuracy and Precision
- Mathematics and Science
Accuracy and Precision
In order to hit the bull’s-eye consistently, you need both accuracy and precision.

21. Significant Figures - Mathematics and Science
The significant figures in a measurement include all of the digits that have been measured exactly, plus one digit whose value has been estimated.

22. Significant Figures - Mathematics and Science
When you multiply measurements, your answer can only have the same number of significant figures as the measurement with the fewest significant figures.

23. Percent Error - Mathematics and Science
You calculate the density of an object to be 9.37 g/cm3. The density of the object is actually 8.92 g/cm3. Calculate your percent error.
Read and Understand
What information are you given?
Experimental value = 9.37 g/cm3
True value = 8.92 g/cm3

24. Percent Error - Mathematics and Science
You calculate the density of an object to be 9.37 g/cm3. The density of the object is actually 8.92 g/cm3. Calculate your percent error.
Plan and Solve
What quantity are you trying to calculate?
Percent error = __
What formula contains the given quantities and the unknown quantity?

25. Percent Error - Mathematics and Science
You calculate the density of an object to be 9.37 g/cm3. The density of the object is actually 8.92 g/cm3. Calculate your percent error.
Plan and Solve
Perform the calculation.
Percent Error = 5.04%

26. Percent Error - Mathematics and Science
You calculate the density of an object to be 9.37 g/cm3. The density of the object is actually 8.92 g/cm3. Calculate your percent error.
Look Back and Check
The answer tells you that your percent error is about 5%. This answer makes sense because the experimental value and the true value were close to each other.

27. Percent Error - Mathematics and Science
Tanya measured the mass of an object to be 187 g. Sam measured the object’s mass to be 145 g. The object’s actual mass was 170 g.
What is Tanya’s percent error?
10.0%

28. Percent Error - Mathematics and Science
Tanya measured the mass of an object to be 187 g. Sam measured the object’s mass to be 145 g. The object’s actual mass was 170 g.
What is Sam’s percent error?
14.7%

29. Mean, Median, and Mode - Mathematics and Science
The mean is the numerical average of the numbers in a list.

30. Mean, Median, and Mode - Mathematics and Science
If an ordered list has an odd number of entries, the median is the middle number in a set of data. If a list has an even number of entries, the median is the sum of the two middle numbers divided by two.

31. Mean, Median, and Mode - Mathematics and Science
The mode is the number that appears most often in a list of numbers.

32. Asking Questions - Mathematics and Science
Before you read, preview the red headings. In a graphic organizer like the one below, ask a what, how, or why question for each heading. As you read, write the answers to your questions.
Questions
Answers
What does estimation have to do with science?
Scientists use estimation when they cannot obtain exact measurements.
What are accuracy and precision?
Accuracy refers to how close a measurement is to the true or accepted value, and precision refers to how close a group of measurements are to each other.
What are significant figures?
The term significant figures refers to the digits in a measurement.
What is percent error?
Percent error is a calculation used to determine how accurate an experimental value really is.
What are mean, median, and mode?
They are ways to calculate an “average.”

33. Links on Math and Science
- Mathematics and Science
Links on Math and Science
Click the SciLinks button for links on math and science.

34. End of Section: Mathematics and Science

35. The Importance of Graphs
- Graphs in Science
The Importance of Graphs
Line graphs are used to display data to show how one variable changes in response to another variable. In this experiment, the responding variable is the time it takes for the water to boil. The manipulated variable is the volume of water in the pot.

36. - Graphs in Science
Plotting a Line Graph

37. Plotting a Line Graph Activity
- Graphs in Science
Plotting a Line Graph Activity
Click the Active Art button to open a browser window and access Active Art about plotting a line graph.

38. Why Draw a Line of Best Fit?
- Graphs in Science
Why Draw a Line of Best Fit?
A line of best fit emphasizes the overall trend shown by all the data taken as a whole.

39. Slope - Graphs in Science
The slope of a graph line tells you how much y changes for every change in x.

40. Car Travel - Graphs in Science
The graph shows the distance a car travels in a one-hour period. Use the graph to answer the questions that follow.

41. Car Travel - Graphs in Science Reading Graphs:
What variable is plotted on the horizontal axis? What variable is plotted on the vertical axis?
Time (min), the manipulated variable, is plotted on the horizontal axis. Distance (km), the responding variable, is plotted on the vertical axis.

42. Car Travel - Graphs in Science Interpreting Data:
How far does the car travel in the first 10 minutes? In 40 minutes?
The car travels 10 km in 10 minutes and 40 km in 40 minutes.

43. Car Travel - Graphs in Science Predicting:
Use the graph to predict how far the car would travel in 120 minutes. Assume the car continues to travel at the same speed.
The car is traveling 1 km per minute. It would travel 120 km in 120 minutes.

44. Car Travel - Graphs in Science Calculating:
Calculate the slope of the graph. What information does the slope provide about the speed of Car 2?
The slope is 1 km/min. The slope provides information about the car’s average speed.

45. Car Travel - Graphs in Science Drawing Conclusions:
Compare the graphs for Car 1 and Car 2. What is the relationship between the steepness of the graph lines and the speed of the cars?
The slope of the graph for Car 1 is 0.5 km/min. Because the distance and time values are marked the same on the two graphs, a steeper line represents a greater speed. Car 2 is traveling twice as fast as Car 1.

46. Using Graphs to Identify Trends
- Graphs in Science
Using Graphs to Identify Trends
Line graphs are powerful tools in science because they allow you to identify trends and make predictions.

47. Building Vocabulary - Graphs in Science
A definition states the meaning of a word or phrase by telling about its most important feature or function. After you read the section, reread the paragraphs that contain definitions of Key Terms. Use all the information you have learned to write a definition of each Key Term in your own words.
Key Terms:
Examples:
coordinate
data point
line of best fit
linear graph
Key Terms:
Key Terms:
Examples:
slope
nonlinear graph
Examples:
graph
The slope of a graph line is how steep the line is.
A graph is a picture of data that reveals patterns or trends.
A coordinate is a point on a graph that is determined by a pair of numbers.
A nonlinear graph is a graph on which the data points do not fall on a straight line.
horizontal axis
A data point on a graph is where an imaginary line from the horizontal axis would meet an imaginary line from the vertical axis.
The horizontal axis is the graph line that runs from left to right.
vertical axis
The vertical axis is the graph line that runs up and down.
The line of best fit on a graph is a smooth line between points that reflects the general pattern of the points.
origin
The origin of a graph is the point where the horizontal and vertical axes meet.
A linear graph is a straight-line graph.

48. End of Section: Graphs in Science

49. Safety in the Lab - Safety in the Science Laboratory
These safety symbols remind you to work carefully when performing labs in this textbook series. Make sure you are familiar with each safety symbol and what it means.

50. In Case of an Accident - Safety in the Science Laboratory
When any accident occurs, no matter how minor, notify your teacher immediately. Then listen to your teacher’s directions and carry them out quickly.

51. Safety in the Science Laboratory
Outlining
As you read, make an outline about science safety that you can use for review. Use the red headings for the main topics and the blue headings for supporting ideas.
Safety in the Science Laboratory
Safety in the Lab
Preparing for the Lab
Performing the Lab
End-of-Lab Procedures
Safety in the Field
In Case of an Accident

52. Links on Laboratory Safety
- Safety in the Science Laboratory
Links on Laboratory Safety
Click the SciLinks button for links on laboratory safety.

53. End of Section: Safety in the Science Laboratory

54. The number that appears most often in a list of numbers
Graphic Organizer
can be a is
Average
Mean
The middle number
Median
Mode
The number that appears most often in a list of numbers
The numerical average

55. End of Section: Graphic Organizer