If the volume of a confined gas is doubled while the temperature remains constant, the pressure will

If the volume of a confined gas is doubled while the temperature remains constant, the pressure will

• A. Remain unchanged
• B. Double
• C. Half
• D. Quadruple

Answer: (C)

At constant temperature with a fixed amount of gas, pressure and volume are inversely related: P ∝ 1/V. This is Boyle’s law, expressed as P1V1 = P2V2. If the volume is doubled, the pressure must drop to half because the same number of gas particles collide with the container walls less often when there’s more space. Mathematically, P2 = P1 × (V1/V2) = P1 × (1/2) = P1/2. For instance, if the initial pressure is 2 atm, doubling the volume would reduce it to 1 atm. The other outcomes would contradict the inverse relationship: keeping pressure unchanged ignores the increased space, doubling pressure would require halving the volume, and quadrupling would require reducing volume to a quarter.

At constant temperature with a fixed amount of gas, pressure and volume are inversely related: P ∝ 1/V. This is Boyle’s law, expressed as P1V1 = P2V2. If the volume is doubled, the pressure must drop to half because the same number of gas particles collide with the container walls less often when there’s more space. Mathematically, P2 = P1 × (V1/V2) = P1 × (1/2) = P1/2. For instance, if the initial pressure is 2 atm, doubling the volume would reduce it to 1 atm. The other outcomes would contradict the inverse relationship: keeping pressure unchanged ignores the increased space, doubling pressure would require halving the volume, and quadrupling would require reducing volume to a quarter.