Question

A biology class wanted to study the effect of different materials on the melting rate of ice. They placed pieces of ice, each with a mass of 10g, onto trays. Group 1 was covered in plastic, group 2 was covered in paper, group 3 was covered in aluminum, and group 4 remained uncovered.

Each piece of ice was allowed to melt for 15 minutes. Then final mass of the ice, minus the melted water, was recorded at the end of the experiment.
Which of the following is the control group in this experiment?

Answer 1

The control group in this experiment is group 4, which remained uncovered.

In an experiment, the control group is the group that does not receive any treatment or manipulation. It serves as a baseline for comparison to the other groups. In this case, the control group is not covered with any material, which means it is not subjected to any additional factors that could affect the melting rate of ice.

By comparing the results of the other groups (group 1 covered in plastic, group 2 covered in paper, and group 3 covered in aluminum) to the control group, the researchers can determine the effect of different materials on the melting rate of ice.

I hope this helps you. :)

Answer 2

The control variable is a group that serves as a baseline for comparision. The independent variable is not applied or only applied at a baseline level.

The independent variable is the covering of the ice with different materials. Because group 4 wasn't covered, it is the control variable.