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Question
Value of universal gas constant (R) is same for all gases. What is its physical significance?
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Solution
Unit of R depends on the units of p, V and T are measured, We know, `R = (pV)/(nT)`
Now, let's say, the pressure is measured in Pascal, per mole volume is measured in m3 and temperature is measured in Kelvin, then. Units of ‘R’ are Pa m3K–1 mol–1. Also, R is work done per mole per kelvin. It’s unit is J K–1 mol–1 (Joule is the unit of work done).
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