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# Floating Ideas

Gaseous chapter frames
Axiomatic’ly
P, V, n, R, T:
Equation “ideal.”
(Think re: gas species’ own
Volumes and actions as
Rule is expanded to
Statement more “real.”)

The 16 November 2020 Twitter poem commemorated a traditionally late-in-semester topic, with a summary of some key equations related to gas chemistry.

“Gaseous chapter frames /
Axiomatic’ly /
P, V, n, R, T: /
Equation ‘ideal.’”

One of the most useful equations in an introductory chemistry course is the ideal gas law, which combines several principles of gas behavior into an equation, “axiomatic’ly”: PV = nRT.  Here, P represents pressure, V represents volume, n represents amount, R is the gas constant, and T represents temperature.

The ideal gas law is a flexible formula that has several useful applications for scientists, letting us both see qualitative relationships (e.g., at constant volume and amount, pressure is directly proportional to temperature) and complete a variety of calculations related to these properties.

“(Think re: gas species’ own /
Volumes and actions as /
Rule is expanded to /
Statement more ‘real.’)”

The ideal gas law is named as such because it idealizes gas behavior, imagining that an atom or molecule of any gas (regardless of chemical identity) will act in the same way as an atom or molecule of any other gas.  Gas particles are envisioned as spheres that undergo efficient collisions at the particulate level, resulting in the big-picture properties modeled by the ideal gas law at the macroscopic level.  The volume of the gas sample is treated as the volume of the gas’s container

Scientists have also developed “real” gas laws, which take gas molecules’ own chemical behaviors into account: the volumes that the gas molecules occupy and the intermolecular forces exhibited by each specific molecule.  In other words, they “think re: gas species’ own volumes and actions,” compiling experimental parameters for a variety of gases to more accurately represent behavior in extreme conditions (such as high pressure).  Multiple real gas equations have been devised.