Henry’s law constant for the molality of methane in benzene at 298 K is 4.27 × 105 mm Hg. Calculate the solubility of methane in benzene at 298 K under 760 mm Hg.

Given-


Henry’s law constant KH = 4.27X 105 mm Hg,


p = 760mm Hg,


Using Henry’s law,





Using the formula of lowering vapour pressure,


Equation 1


Since, <<<, the Equation 1 is rewritten as,



where and = molarity of benzene






Thus, the solubility of methane in benzene is 0.023 moles


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