General Science Test Flashcards

What is the difference between a physical change and a chemical change?

Answer: Physical changes alter matter's form without changing its chemical composition; chemical changes produce new substances

A physical change alters the form, shape, or state of matter without changing its chemical identity (e.g., melting ice). A chemical change transforms matter into new substances with different chemical compositions (e.g., burning wood).

What is the function of the mitochondria in a cell?

Answer: Produce ATP (adenosine triphosphate) through cellular respiration

Mitochondria are the cell's powerhouses — they generate ATP (the cell's primary energy currency) through cellular respiration, converting glucose and oxygen into usable energy, carbon dioxide, and water.

Which of the following best describes Newton's Third Law of Motion?

Answer: For every action, there is an equal and opposite reaction

Newton's Third Law states that for every action force, there is an equal magnitude but opposite direction reaction force. Forces always occur in pairs between two interacting objects.

What is the pH scale, and what pH value indicates a neutral solution?

Answer: pH measures acidity/basicity on a scale of 0-14; pH 7 is neutral

The pH scale measures the hydrogen ion concentration in a solution on a scale from 0 to 14. pH 7 is neutral (pure water), pH below 7 is acidic, and pH above 7 is basic (alkaline).

What is the primary role of the ozone layer in Earth's atmosphere?

Answer: Absorb most of the sun's harmful ultraviolet (UV) radiation

The ozone layer (O3) in the stratosphere absorbs most of the sun's harmful ultraviolet radiation, particularly UV-B and UV-C wavelengths, protecting life on Earth from radiation damage.

Which type of rock forms when molten rock (magma or lava) cools and solidifies?

Answer: Igneous rock

Igneous rock forms when molten rock (magma below ground or lava above ground) cools and solidifies. The word 'igneous' comes from the Latin word for fire.