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# 18.3: The Universal Gas Constant

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If you had an ideal gas, all you would have to do is to measure its pressure, its temperature, and the volume occupied by a mole, for then PV = RT. (Measuring P and T is relatively easy. Measuring the volume occupied by a mole is less so.) In real life, however, we have to make measurements on real gases. What has to be done is to measure the product PV (at a given temperature) at progressively lower and lower pressures, and extrapolate the value of PV/T to the limit of zero pressure. (See notes in Chapter 6 on the compression factor.)

This page titled 18.3: The Universal Gas Constant is shared under a CC BY-NC license and was authored, remixed, and/or curated by Jeremy Tatum.

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