Which law states the volume is inversely related to pressure at constant temperature?

• A. Charles' Law
• B. Gay-Lussac's Law
• C. Synthesis
• D. Boyle's Law

Answer: (D)

At a fixed temperature, the amount of gas stays the same, so volume and pressure move in opposite directions. When you compress the gas and reduce its volume, more frequent collisions with the container walls raise the pressure. If you enlarge the volume, collisions become less frequent and the pressure drops. This inverse relationship is described by PV = constant, so pressure and volume are inversely related when temperature and amount of gas don’t change. That is Boyle's Law. The other options involve different relationships: volume with temperature at constant pressure (Charles' Law), pressure with temperature at constant volume (Gay-Lussac's Law), or a chemical reaction (synthesis).