PADI Divemaster Certification Practice Exam

What happens to the volume of gas if temperature is raised in a flexible container?

1. The volume decreases

2. The volume remains constant

3. The volume increases

4. The volume fluctuates unpredictably

The correct answer is: The volume increases

When the temperature of a gas in a flexible container is raised, the volume of the gas increases. This phenomenon is described by Charles's Law, which states that at constant pressure, the volume of a gas is directly proportional to its absolute temperature. As the temperature rises, the kinetic energy of the gas molecules increases, causing them to move more vigorously and collide with the walls of the container with greater force. In the case of a flexible container, such as a balloon, this increased molecular movement pushes against the flexible walls, allowing the container to expand and accommodate the higher volume of gas. This principle is foundational in understanding the behavior of gases and is crucial for divers and divemasters, who must consider how gas volumes change with pressure and temperature during dives. Understanding these concepts helps in managing buoyancy and the proper use of gas supplies underwater.