In the context of the Ideal Gas Law, why is it important to remove oil from a low-pressure system operating at 130 °F?

• A. Oil acts as a catalyst, causing the gas to decompose at low pressure.
• B. Oil can vaporize at high temperatures and low pressures, potentially contaminating the gas and affecting pressure readings.
• C. Oil increases the pressure of the system by reacting with the gas.
• D. Oil decreases the temperature of the system, making the Ideal Gas Law invalid.

Answer: (B)

Verified step by step guidance

1. Understand the Ideal Gas Law, which is expressed as \(P V = n R T\), where \(P\) is pressure, \(V\) is volume, \(n\) is the number of moles of gas, \(R\) is the gas constant, and \(T\) is temperature in Kelvin.
2. Recognize that in a low-pressure system operating at elevated temperatures (130 °F), substances like oil can vaporize because their vapor pressure increases with temperature and decreases with pressure.
3. Realize that if oil vaporizes, it introduces additional vapor-phase molecules into the system, which can contaminate the gas mixture and alter the number of moles \(n\) of the ideal gas being measured.
4. Understand that this contamination affects the accuracy of pressure readings and the assumptions of the Ideal Gas Law, since the gas is no longer pure and the measured pressure includes contributions from oil vapor.
5. Therefore, removing oil from the system is important to maintain the integrity of the gas sample and ensure that the Ideal Gas Law applies correctly without interference from vaporized oil.