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