A sealed balloon filled with air that has volume of 6 cubic inches at 99 feet will have a volume of _____ cubic inches at 33 feet

A sealed balloon filled with air that has volume of 6 cubic inches at 99 feet will have a volume of _____ cubic inches at 33 feet

• A. 3
• B. 6
• C. 12
• D. 24

Answer: (C)

Gas volume is inversely related to pressure when temperature is constant. This is Boyle’s law: P1V1 = P2V2 for a fixed amount of gas. Underwater, pressure increases with depth because of the water column plus atmospheric pressure. At 99 feet, the balloon experiences about 4 atmospheres of pressure (1 atm at the surface plus about 3 atm from the water). At 33 feet, the pressure is about 2 atmospheres (1 atm surface plus about 1 atm from the water). The gas inside the balloon stays the same, so V2 = (P1V1)/P2 = (4 atm × 6 in³) / 2 atm = 12 in³. Therefore, the volume at 33 feet is 12 cubic inches.

Gas volume is inversely related to pressure when temperature is constant. This is Boyle’s law: P1V1 = P2V2 for a fixed amount of gas.

Underwater, pressure increases with depth because of the water column plus atmospheric pressure. At 99 feet, the balloon experiences about 4 atmospheres of pressure (1 atm at the surface plus about 3 atm from the water). At 33 feet, the pressure is about 2 atmospheres (1 atm surface plus about 1 atm from the water).

The gas inside the balloon stays the same, so V2 = (P1V1)/P2 = (4 atm × 6 in³) / 2 atm = 12 in³. Therefore, the volume at 33 feet is 12 cubic inches.