Humber Admissions Practice Test

What does Boyle's Law describe about the relationship between pressure and volume of a gas?

1. A direct relationship under constant temperature

2. An inverse relationship under constant temperature

3. A variable relationship with changing temperature

4. No relationship when temperature is constant

The correct answer is: An inverse relationship under constant temperature

Boyle's Law states that the pressure of a gas is inversely proportional to its volume when the temperature is held constant. This means that as the volume of a gas decreases, its pressure increases, and vice versa, as long as the temperature doesn't change. This relationship can be mathematically represented as PV = k, where P is the pressure, V is the volume, and k is a constant. This inverse relationship is fundamental to understanding how gases behave under varying conditions. For instance, if a gas is compressed (making the volume smaller), its pressure will rise. Conversely, if the gas expands (increasing the volume), the pressure will drop. The other choices represent misunderstandings of Boyle's Law. A direct relationship would mean that both pressure and volume increase or decrease together, which contradicts the inverse relationship stated in Boyle's Law. A variable relationship with changing temperature doesn't specifically tie to Boyle's Law, but rather describes conditions outside its scope. Similarly, suggesting there is no relationship when temperature is constant disregards the foundational principles of Boyle's Law.