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ACT Science - The Content Knowledge Questions

The Science section of the ACT will generally feature a few (1-3) questions requiring outside science knowledge. Many questions that initially seem to require outside knowledge can actually be answered by finding words in italics in the passage to obtain definitions.

The June 2017 test required students to know biological classification - that species will follow genus. The full rundown is kingdom, phylum, class, order, family, genus, and species in case you were wondering.

Below you will find our compilation of outside knowledge topics that have been tested over the years. We did our best to be thorough, but acknowledge a few things may have slipped through the cracks. We are confident that reviewing this material will put you in a better position to attack the content knowledge questions on the ACT science. (Please accept our apologies for lack of superscript and subscript formatting.)

She is using test tubes to carry out an experiment.

In the realm of chemistry, students have been expected to know the difference between reactants and products, that products are on the right side of an equation. Balanced equations feature coefficients in front of each formula to satisfy the law of conservation of mass. Chemical quantities can be related, scaled up, or scaled down using proportions and coefficients. When it comes to atoms, protons and neutrons are located inside the nucleus and electrons can be found outside the nucleus. While students are not required to recall Avogadro's number (6.022x10^23), they should have a basic understanding of the mole concept and molar mass. Mass can be measured with a balance; volume can be measured with a graduated cylinder. Basic familiarity with the pH scale is essential. Yes, that pun was intended. Students need to know that acidity increases as pH decreases and that 7 represents a neutral pH at standard room temperature. Know that heat flows from higher temperature substances to lower temperature substances. If the temperature is below the freezing point, the substance is a solid. If the temperature is above the boiling point, the substance is a gas. If the temperature is between the freezing point and the boiling point, the substance is a liquid. Fun fact, the freezing point is the same as the melting point. Water (H2O) freezes at 0 degrees Celsius and boils at 100 degrees Celsius.

The train was moving at such a high velocity.

In the realm of physics, students have been expected to know the difference between kinetic energy (motion) and potential energy (position/stored) and understand the law of conservation of energy. As temperature increases, particles move faster. Some helpful equations are KE=(1/2)mv^2 and PE=mgh. Students should know that gravity is a downward force while buoyant force is upward. Students should also know that momentum is the product of mass and velocity. Remember that velocity is speed (change in position over change in time) with direction and acceleration is the change in velocity over the change in time. Inertia is an object's tendency to remain at rest or in motion. Students should know that density (mass/volume) will determine if an object will sink or float; if an object is more dense than what it is in, it will sink. When it comes to waves, the amplitude is the height from the center line to the peak and the wavelength is the distance from peak to peak.

It's a plant capable of carrying out photosynthesis.

In the realm of biology, students have been expected to know that XX represents a female and XY represents a male (guy) and associate egg and sperm as the gametes with female and male, respectively. Students should commit to memory the following details about photosynthesis: occurs in chloroplasts in plant cells, features carbon dioxide plus water plus light as reactants, and produces glucose (a sugar) and oxygen. Familiarity with the terms mitosis (cell division) and metamorphosis (think caterpillar to butterfly) should also be helpful. When classifying, the full rundown is kingdom, phylum, class, order, family, genus, and species.

When it comes to experimental design, students should know that a control is an untreated sample and that only one independent variable (x-axis) should be changed at a time. The dependent variable (y-axis) can be measured as a result. Remember, it's all about assigning blame.

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