Science
What this subtest measures
Science tests integrated high-school biology, chemistry, physics, and earth science, often through short data sets, verbally described diagrams, and experimental scenarios. Expect cell structure and genetics; ecology and evolution; atomic structure, bonding, and stoichiometry; acids and bases; motion, forces, energy, and circuits; waves; plate tectonics, weather, and climate.
Core rules to apply
- Biology: relate structure to function; track alleles with Punnett squares; distinguish mitosis from meiosis; identify energy flow and trophic levels.
- Chemistry: balance equations before using mole ratios; use the periodic table for valence and trends; know that pH below 7 is acidic.
- Physics: draw a free-body diagram; apply F = ma and conservation of energy; use sign conventions consistently; use V = IR for circuits.
- Earth science: link plate boundaries to earthquakes, volcanoes, and mountain belts; distinguish weather from climate.
- Experimental design: identify independent, dependent, and controlled variables; a hypothesis is testable, while a theory is a well-supported explanation.
Worked example
A 2 kg cart experiences a net force of 6 N. What is its acceleration? Use F = ma, so a = F/m = 6 N / 2 kg = 3 m/s². The reasoning matters: “net force” means the sum of forces, not any single applied force. If friction were also present, you would subtract it before dividing.
Traps that cost marks
- Using mass and weight interchangeably; weight is mg and is measured in newtons.
- Forgetting coefficients in mole ratios or skipping equation balancing.
- Mixing units such as cm with m or grams with kg before calculating.
- Treating “theory” as a guess or “hypothesis” as a proven fact.
- Ignoring control groups or confounding variables in experimental items.