A research team records the compressibility factor for neon gas at over a pressure…
CHEMISTRY · Multi-part · A Level · Chemistry · Amount of substance · Amount of substance
Problem
A research team records the compressibility factor Z=nRTPV for neon gas at 298K over a pressure range from 1atm to 2000atm. Their data show that Z<1 at moderate pressures (up to roughly 400atm) but rises well above unity as the pressure approaches 2000atm.
Answer the following questions about the observed behavior of neon gas.
(a) Describe, in terms of molecular-level interactions, why Z drops below unity at moderate pressures for neon.
(b) Explain why Z increases above unity at very high pressures and identify the dominant molecular property responsible for this upward deviation.
(c) Sketch qualitatively the expected form of a Z versus P plot (pressure on the horizontal axis, Z on the vertical axis) for neon at 298K, clearly indicating the regions where attractive and repulsive effects dominate.