The first step of science is making observations about the world.

Question

i. Observations involve looking for interesting patterns or cause-and-
effect relationships.
c. The second step is to create a tentative explanation for observed
phenomena. This is called a ___________________.
i. Useful hypotheses involve testable predictions. Hypotheses can be
refined and adjusted as needed.
d. The third step is to design and experiment that will test the hypothesis
i. Experimental design is a critical part of the scientific process.
Experiments that are carefully and purposefully designed are most
likely to show cause-and-effect relationships between variables.
Additionally, it is critical that experimental results can be
reproduced when the experiment is repeated.
ii. Controlling variables makes experiments more powerful
iii. Define each of the following elements of experiments:
● Experimental group
● Control group
● Variables
○ Independent variable
○ Dependent variable
● Why is it important to control variables in an experiment?

Answer 1

Let's fill in the blank and define the elements of experiments as requested:

c. The second step is to create a tentative explanation for observed phenomena. This is called a hypothesis.

Now, let's define the elements of experiments:

Elements of Experiments:

• Experimental Group: This is the group in an experiment that receives the treatment or the independent variable being tested. This group is compared to the control group to assess the effect of the treatment.

• Control Group: This group does not receive the treatment or independent variable and is kept under the same conditions as the experimental group. It serves as a baseline to compare the effects of the treatment.

• Variables:

  • Independent Variable: This is the variable that is changed or manipulated by the researcher to observe its effects on the dependent variable. It is the presumed cause in a cause-and-effect relationship.

  • Dependent Variable: This is the variable that is measured or observed in the experiment. It is expected to change in response to changes in the independent variable, making it the effect in a cause-and-effect relationship.

Importance of Controlling Variables:

Controlling variables is essential in an experiment because:

1. Reduces Confounding Factors: By controlling variables, researchers can isolate the effects of the independent variable on the dependent variable, reducing the chance that other variables will influence the outcome.

2. Enhances Validity: Controlled variables increase the validity of the results, making it clearer whether changes in the dependent variable are due to the manipulation of the independent variable.

3. Improves Reproducibility: When variables are controlled, it becomes easier for other researchers to repeat the experiment and verify the results, which is a fundamental aspect of the scientific method.

4. Enables Accurate Comparisons: Control groups and controlled conditions allow for valid comparisons between groups, enhancing the reliability of conclusions drawn from the data.

By carefully controlling variables, scientists can draw more accurate conclusions and contribute to a better understanding of the phenomena being studied.