Question

shakita wants to know if the ph of an open can of soda changes over time. to test this, she designs an experiment that will involve the following steps.

1. open a can of soda and measure the ph.
2. allow the open soda can to rest undisturbed on a level countertop at room temperature.
3. measure the ph of the open soda can every day at the same time for ten consecutive days.

what is the outcome variable (dependent variable) in shakita’s experiment?
a. the number of days
b. the ph of the soda
c. the temperature of the room
d. the type of soda

Explanation:

In an experiment, the dependent variable is what is being measured or observed and depends on the independent variable. Here, Shakita is testing how the pH of the open soda (dependent variable) changes over time (independent variable, the number of days). The room temperature and type of soda are controlled variables, and the number of days is the independent variable. So the dependent variable is the pH of the soda.

Answer:

B. the pH of the soda