Science: Graphing Scientific Data Choosing the Right Chart Type
Selecting effective charts for experimental results
Science: Graphing Scientific Data Choosing the Right Chart Type
Selecting effective charts for experimental results
Science - Grade 9-12
- 1
A biology student measures the height of a bean plant every two days for three weeks. Which chart type would best show how the plant's height changes over time? Explain your choice.
Look for whether the independent variable is time.
A line graph would be best because the data are measurements taken over time. A line graph makes it easy to see the trend in plant height across the three weeks. - 2
A chemistry class records the final temperature of four different liquids after each liquid is heated for the same amount of time. Which chart type would best compare the final temperatures? Explain your choice.
A bar graph would be best because it compares one measured value across separate categories. Each liquid can have its own bar showing its final temperature. - 3
A student wants to show the percentage of gases in Earth's atmosphere, such as nitrogen, oxygen, argon, and carbon dioxide. Which chart type would best show the parts of the whole atmosphere? Explain your choice.
Use this chart type when all categories add up to 100 percent.
A pie chart would be best because the data show percentages that make up one whole. Each slice can represent the proportion of one gas in the atmosphere. - 4
A physics student measures the distance traveled by a cart at different times as it rolls down a ramp. The student wants to analyze the relationship between time and distance. Which chart type should be used? Explain your choice.
Consider whether the data points are ordered and connected by time.
A line graph or scatter plot with a best-fit curve would be appropriate because both variables are numerical. Since the measurements are connected over time, a line graph can show how distance changes as time increases. - 5
A marine scientist counts the number of fish species found at five different reef sites. Which chart type would best compare the species counts among the reef sites? Explain your choice.
A bar graph would be best because the reef sites are separate categories. The height of each bar can show the number of species found at each site. - 6
A student measures enzyme activity at different pH levels: 3, 5, 7, 9, and 11. Which chart type would best show how enzyme activity changes with pH? Explain your choice.
Use a graph that can show a pattern across ordered numerical values.
A line graph or scatter plot would be best because pH and enzyme activity are numerical variables. This type of graph can show the pattern of activity across the pH range. - 7
A survey asks 200 students to choose their favorite science subject: biology, chemistry, physics, environmental science, or astronomy. Which chart type would best display the number of students choosing each subject? Explain your choice.
A bar graph would be best because the science subjects are categories. A bar graph can clearly compare how many students chose each subject. - 8
A climate scientist wants to show average global temperature from 1880 to the present. Which chart type should be used to show the long-term trend? Explain your choice.
A trend over many years is usually shown with connected data points.
A line graph should be used because the data are continuous measurements across many years. A line graph makes long-term warming or cooling trends easier to see. - 9
A student compares the masses of pennies made before 1982 and after 1982 using many measurements from each group. The student wants to show the distribution of masses in the two groups. Which chart type would be useful? Explain your choice.
Choose a chart that shows how numerical measurements are spread out.
A histogram or box plot would be useful because the student is examining distributions of numerical measurements. A box plot is especially useful for comparing the center and spread of two groups. - 10
A researcher records the wing length and body mass of 50 birds to see whether larger birds tend to have longer wings. Which chart type is most appropriate? Explain your choice.
A scatter plot is most appropriate because both variables are numerical and the researcher wants to look for a relationship between them. Each bird can be shown as one point on the graph. - 11
A geology class wants to display the relative percentages of rock types found in one sample: igneous, sedimentary, and metamorphic fragments. Which chart type should they use? Explain your choice.
This works only when the categories represent portions of a single total.
A pie chart should be used because the data are parts of one whole sample. Each slice can show the percentage of the sample made of each rock type. - 12
A student tests how the concentration of salt in water affects the boiling point. The student uses five salt concentrations and records the boiling point for each one. Which chart type would best show the relationship? Explain your choice.
A scatter plot or line graph would be best because both salt concentration and boiling point are numerical variables. The graph can show whether boiling point changes as concentration increases. - 13
A lab group records the number of bacteria colonies in a petri dish every hour for 12 hours. Which chart type would best show the change in colony count over time? Explain your choice.
When time is on the x-axis, a line graph is often useful.
A line graph would be best because the data show change over time. The line can help reveal whether the colony count increases slowly, rapidly, or levels off. - 14
A student has data showing the number of earthquakes in each magnitude range: 2.0 to 2.9, 3.0 to 3.9, 4.0 to 4.9, and 5.0 to 5.9. Which chart type best shows the frequency of earthquakes in these numerical intervals? Explain your choice.
Numerical intervals are often shown with bars that touch.
A histogram would be best because the data are frequencies grouped into numerical intervals. Each bar represents a magnitude range, and the bar height shows how many earthquakes occurred in that range. - 15
A student makes a graph with animal species on the x-axis and average heart rate on the y-axis, using connected points. The species are mouse, rabbit, dog, horse, and elephant. Explain why the connected line may be misleading and identify a better chart type.
The connected line may be misleading because animal species are separate categories, not a continuous variable. A bar graph would be better because it compares average heart rate across different species.