The application of solvent extraction in qualitative analysis

46 THE APPLICATION OF SOLVENT EXTRACTION IN QUALITATIVE ANALYSIS A few examples of the application of solvent extraction in qualitative analysis are as follows  

Example 38 Ten milligrams iodine are suspended in 12 ml water, and shaken with 2 ml CC14 until equilibrium is reached. Calculate the weight of iodine remaining in the aqueous layer. 

Let x be the weight (in milligrams) of iodine which remains in the aqueous phase. Its concentration will become 

In the CC14 10-x mg iodine will be found, its concentration being 

If the CC14 layer is withdrawn with the aid of a separatory funnel and the residual aqueous layer is shaken with a second 2 ml batch fresh CC14, the quantity of iodine still remaining in the aqueous layer, y, can be computed from the equation 

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