ACS Chemistry Practice Exam 2025 – The All-in-One Guide to Exam Success!

Boyle's Law describes the relationship between the pressure and volume of a gas when the temperature is held constant. It states that the product of pressure (P) and volume (V) remains constant for a given amount of gas as long as the temperature does not change. This relationship can be expressed mathematically as PV = constant, which indicates that if the volume increases, the pressure must decrease, and vice versa, so that their product remains unchanged.

The concept behind this law arises from the kinetic molecular theory, which explains that gas particles are in constant motion. When the volume of a gas decreases, the particles have less space to move around, leading to more frequent collisions with the walls of the container, which results in increased pressure. Conversely, if the volume increases, the particles can move more freely, resulting in less frequent collisions and decreased pressure.

The other answer choices provide different interpretations or representations of the relationship that do not align with Boyle's Law. For instance, P + V = constant would suggest that the sum of pressure and volume remains unchanged, which does not reflect the interdependent nature of pressure and volume described by Boyle's Law. Similarly, P/V = constant implies that the ratio of pressure to volume is constant, instead of their product