A sample of diethyl ether is added to a mixture of water and octanol at a temperature of 293 K. If the equilibrium concentration of diethyl ether in the aqueous layer is 21 mmol dm^-3, what is the concentration of the organic layer? The value of the coefficient for the partition of diethyl ether between octanol and water at this temperature is, expressed as a logarithm, log₁₀K = 0.83.

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Quizplus · Accepted Answer

The partition coefficient K is given by the ratio of concentrations in the organic layer to the aqueous layer. With log10K = 0.83, K = 10^0.83 ≈ 6.76. Therefore, the concentration in the organic layer is 21 mmol dm^-3 * 6.76 = 142 mmol dm^-3 = 0.142 mol dm^-3, which is closest to 0.14 mol dm^-3.

A Sample of Diethyl Ether Is Added to a Mixture