Scientific Measurement and Lab Skills

Translating experimental findings from data points to visual representations, like graphs, is essential to determining the relationship between two or more properties. These properties are called variables. When there are two variables, a graph created from the data is called two-dimensional. The graph has two axes. The independent variable is plotted on the x-axis, and the dependent variable is plotted on the y-axis.

Take, for example, this sample data for the temperature and volume of a gas. The volume of the gas depends on the temperature. Thus, we would plot the measured temperature on the x-axis and the volume on the y-axis.

When there are several data points with the same x-value, like if we measured the volume several times at one temperature, we also calculate the standard deviation of those measurements. The standard deviation is a statistical value, which indicates the amount of variation present in a set of values.

Standard deviation is calculated using this formula, where n is the number of data points, x bar is the mean value of the data points, and x_i represents each individual data point. You can compute the standard deviation by hand, or a spreadsheet program can ca