When we are trying to identify dependent and independent variables in an experiment, it's important to understand the nature of each variable and their relationship.
1. Independent Variable: This is the variable that is manipulated or controlled in an experiment. It is the cause that influences changes. In this case, the experiment measures the amount of carbon dioxide ([tex]$\text{CO}_2$[/tex]) produced over a period of time. Here, "Time" is something that is systematically changed or recorded by the experimenter.
2. Dependent Variable: This is the variable being observed or measured. It's the effect or outcome that is dependent on the changes of the independent variable. In our experiment with yeast, we measure how much [tex]$\text{CO}_2$[/tex] is produced as time progresses.
Given data:
[tex]\[
\begin{array}{|c|c|}
\hline
\text{Time (min)} & \text{CO}_2 \text{ Produced (mL)} \\
\hline
5 & 4.1 \\
\hline
10 & 5.9 \\
\hline
15 & 8.2 \\
\hline
\end{array}
\][/tex]
Looking at the data, we see that the amount of [tex]$\text{CO}_2$[/tex] produced is recorded at different time intervals. This indicates that we are observing how [tex]$\text{CO}_2$[/tex] production changes in response to the passage of time.
Therefore, based on the nature of the variables:
- Independent Variable: Time (min) – This is what we control or measure at fixed intervals.
- Dependent Variable: CO₂ Produced (mL) – This is what we measure as an outcome of the yeast’s activity over time.
Hence, the dependent variable is the amount of CO₂ produced.
