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R\textup{, gas constant}=\frac{8.31\textup{ joules}}{\textup{mole}\cdot\textup{kelvin}}=0.0821\frac{\textup{liter}\cdot\textup{atm}}{\textup{mole}\cdot\textup{kelvin}}=8.31\frac{\textup{volts}\cdot\textup{coulombs}}{\textup{mole}\cdot\textup{kelvin}}