What is the purpose of a control group in an experiment?

The purpose of a control group in an experiment is to serve as a standard for comparison that helps to isolate the effects of the experiment's variable. By having a control group, researchers can measure how the experimental conditions affect the results by comparing them to a group that is not subjected to the experimental treatment. This allows for a clearer understanding of the changes attributable to the independent variable, as the control group is kept under the same conditions as the experimental group, except for the variable being tested.

This systematic comparison enables scientists to draw more accurate conclusions about the relationship between the variable being tested and the observed outcomes. Without a control group, it would be challenging to determine whether the results were due to the manipulation of the experimental variable or other external factors.