Graphing

Graphing Two students work together to complete a study to determine how the amount of water given to plants affects the plant growth. Each student is then responsible for creating a graph to demonstrate the relationship between the variables. Compare the two graphs given below: 110 125

Graphing 110 125

Graphing Graphs are drawn so that we can easily see relationships between variables. As previously demonstrated, there are certain properties that a graph should possess in order to best show these relationships. It is these traits that will be assessed when you create graphs for this class.

Graphing The title of the graph clearly relates to the information displayed on the graph. The title should be in the form of responding variable vs. manipulated variable The title should be clearly displayed at the top of the graph.

Graphing Lab Scenario: An experiment was done to see if salt affects the boiling point of water. 100 mL of water was mixed with a different amount of salt for each trial. The water was then heated until boiling. The temperature that the water boiled at was recorded in degrees Celsius. Write a title for the graph that would be plotted for the experiment. Boiling point of water versus amount of salt added

Graphing The independent (manipulated) variable is placed on the x-axis and the dependent (responding) variable is placed on the y-axis. On a graph, the horizontal axis is the x-axis The vertical axis is the y-axis.

Graphing Lab Scenario: An experiment was done to see if salt affects the boiling point of water. 100 mL of water was mixed with a different amount of salt for each trial. The water was then heated until boiling. The temperature that the water boiled at was recorded in degrees Celsius. Which variable would go on the x-axis? Amount of salt added Which variable would go on the y-axis? Boiling Point

Graphing 3.The data was used to choose an appropriate consistent interval to number the x-axis and y-axis. You must determine how to number the axes with numbers called increments. The increments on the axes do not have to start at zero The increments on the x-axis do not have to be equal to the increments on the y-axis

Graphing Use the data given and the number of blocks on your graph paper to determine the increments you will use. Increment Practice Worksheet

Graph 1 Graph 1 Mass vs. Volume Volume(mL) Mass(g) 25.0 35.0 30.0 42.0 25.0 35.0 30.0 42.0 35.0 49.0 40.0 56.0 45.0 63.0

Graph 2 Sun exposure (hr) Height(mm) 1.0 1 2.0 8 3.0 27 4.0 64 5.0 125 Graph 2 Plant Height vs. Sun exposure Sun exposure (hr) Height(mm) 1.0 1 2.0 8 3.0 27 4.0 64 5.0 125

Graph 3 Age (years) Distance Walked (km) 20 20 30 15 40 12 50 8 60 5 Graph 3 Distance Walked vs. Age Age (years) Distance Walked (km) 20 20 30 15 40 12 50 8 60 5 70 1

Graphing Use the data given and the number of blocks on your graph paper to determine the increments you will use. Boiling Point as a function of amount of salt added for 100 mL of water Salt Added (g) Boiling Point (oC) 0.0 100.00 5.0 100.75 10.0 101.75 15.0 102.50 20.0 103.50

Graphing 4. Numbers on each graph axis are spaced evenly.

Graphing When labeling numbers on the axes, do not list your data values, rather list regular increments. Boiling Point as a function of amount of salt added for 100 mL of water Salt Added (g) Boiling Point (oC) 0.0 100.00 5.0 100.75 10.0 101.75 15.0 102.50 20.0 103.50

Graphing 5. All parts of the graph are labeled (each axis, including units).

Graphing 6. The set of data is plotted on the graph completely and accurately.

Graphing Once the points have been plotted, it is often useful to connect each value with a best fit line.

Graphing These should not connect the dots, but instead show the general relationship between the plotted variables.

Graphing DIRECT linear relationship As X increases, Y increases Possible Relationships DIRECT linear relationship As X increases, Y increases

Graphing INVERSE linear relationship As X increases, Y decreases Possible Relationships INVERSE linear relationship As X increases, Y decreases

Graphing Possible Relationships Curvilinear relationship

Graphing After graphing your data, write a caption for the graph that includes the type of relationship and a conclusion.