When three moles of helium is mixed with one mole of neon at constant temperature and pressure (25°C, 1 atm), the entropy of mixing (in $\mathrm{JK^{-1}}$, rounded off to two decimal places) is ____ (Given: $R = 8.314\ \mathrm{JK^{-1}\,mol^{-1}}$)
Answer
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