Which of the following observations best supports Boyle's Law?

• A. When the pressure of a gas increases at constant volume, its temperature increases.
• B. When the amount of gas increases at constant temperature and pressure, its volume remains unchanged.
• C. When the temperature of a gas increases at constant pressure, its volume increases.
• D. When the volume of a gas decreases at constant temperature, its pressure increases.

Answer: (D)

Verified step by step guidance

1. Recall Boyle's Law, which states that for a given amount of gas at constant temperature, the pressure of the gas is inversely proportional to its volume. Mathematically, this is expressed as \(P \times V = k\), where \(P\) is pressure, \(V\) is volume, and \(k\) is a constant.
2. Understand that Boyle's Law applies only when the temperature and the amount of gas are held constant. This means any change in pressure must be accompanied by an opposite change in volume to keep the product \(P \times V\) constant.
3. Analyze each observation to see if it fits the condition of constant temperature and amount of gas, and whether pressure and volume change inversely.
4. Identify that the observation 'When the volume of a gas decreases at constant temperature, its pressure increases' directly reflects the inverse relationship between pressure and volume described by Boyle's Law.
5. Conclude that this observation best supports Boyle's Law because it matches the law's condition and the inverse relationship between pressure and volume.