Question

Julie sees commercials for antibacterial products and sets up an experiment to study the effectiveness of antibacterial soap. Identify the experimental variable and three controlled variables:

DEPENDENT VARIABLE:

a) Bacterial growth

b) Antibacterial soap

c) Experiment procedure

d) Julie's hypothesis

Answer 1

The dependent variable in Julie's experiment is the bacterial growth, and the controlled variables include the type of antibacterial soap, the experiment procedure, and Julie's hypothesis.

Step-by-step explanation:

The dependent variable in Julie's experiment is the bacterial growth. This is the variable that she will be measuring and observing to determine the effectiveness of the antibacterial soap. The controlled variables in this experiment would include:

1. The type of antibacterial soap used. Julie should ensure that she is using the same brand and type of soap for each trial to eliminate any potential variations in effectiveness.
2. The experiment procedure. Julie should follow the same procedure for each trial, including the duration of exposure to the soap and the method of measuring bacterial growth.
3. Julie's hypothesis. This is the statement she makes about the expected outcome of the experiment, which should remain constant throughout the experiment.