Scientific Inquiry and Process Skills
What this domain tests
The Scientific Inquiry and Process Skills domain asks you to reason like a scientist: frame testable questions, design controlled investigations, choose measurements, interpret tables and graphs, and decide whether evidence supports a claim. Expect items on variables, reliability and validity, error, SI units, data representation, and the relationship among hypothesis, prediction, and conclusion.
Core rules
- An experiment manipulates the independent variable, measures the dependent variable, and holds other factors constant as controlled variables.
- A control group provides a baseline; repeated trials reduce random error, while calibration reduces systematic error.
- Accuracy is closeness to the true value; precision is consistency among measurements.
- A valid conclusion follows from the data and acknowledges uncertainty. Correlation alone does not establish causation.
- Use appropriate SI units and label graph axes with quantity and unit.
Worked example
A student tests whether fertilizer affects plant height. She grows 20 identical seedlings in the same soil, light, and temperature; ten receive fertilizer and ten receive water only. Height after four weeks is measured with a ruler. The fertilizer amount is the independent variable, height is the dependent variable, and light, temperature, soil, and water volume are controlled. The water-only group is the control. If the fertilized group is taller on average and the difference is consistent across trials, the data support the prediction; they do not prove a universal law.
Traps
Do not confuse independent and dependent variables when the question describes the setup. Do not call a control group a controlled variable. Watch for confounding variables, such as differing light, that weaken causal claims. Finally, distinguish a hypothesis from a prediction and avoid absolute language such as 'proves'.