Which of the following correctly states the impact of pressure on the behavior of real gases compared to ideal gases?
At low pressure, real gas particles do not exert any force on the container, so they exert less pressure than ideal gases.
At high pressure, real gas particles take up more of the available space, so their volume is greater than ideal gases.
At low pressure, real gas particles expand to fill the container so their volume cannot be measured compared to ideal gases.
At high pressure, real gas particles are squeezed together, so they take up less volume than ideal gases.
The correct answer and explanation is :
The correct statement is:
“At high pressure, real gas particles take up more of the available space, so their volume is greater than ideal gases.”
Explanation:
To understand why this statement is correct, it’s important to understand the key differences between real gases and ideal gases.
- Ideal Gas Behavior:
- An ideal gas is a theoretical concept that assumes gas molecules do not interact with each other, and their individual volumes are negligible compared to the container volume.
- The ideal gas law (PV = nRT) assumes that gas molecules have perfectly elastic collisions and that their volume and intermolecular forces do not affect the behavior of the gas.
- Real Gas Behavior:
- Real gases, on the other hand, exhibit behavior that deviates from ideal gas law predictions, especially at high pressures and low temperatures.
- At high pressures, gas molecules are compressed closer together. This results in a significant increase in intermolecular forces (such as attraction or repulsion), which reduces the effective volume that the gas molecules can occupy. As a result, the gas does not behave ideally. Real gases exhibit a larger volume than predicted by the ideal gas law because the molecules have physical volume and interact with each other.
- High Pressure and Volume:
- Under high pressure, the volume of a real gas is larger than that predicted by the ideal gas law because the volume occupied by the gas molecules themselves becomes more significant.
- The ideal gas law doesn’t account for the finite volume of gas molecules or their intermolecular forces. Therefore, real gases at high pressure deviate from the ideal gas behavior by taking up more space.
- Low Pressure:
- At low pressure, the deviations between ideal and real gases are minimal because the gas molecules are far apart, and intermolecular forces have less effect. In this scenario, real gases behave more like ideal gases.
Conclusion:
The correct statement highlights that, at high pressure, real gases take up more space than ideal gases due to intermolecular forces and the finite volume of gas molecules.