Solvent Extraction Using Safe and Commonly Available Materials To Demonstrate the Difference in Solubility of Two Mixed Solutes

Abstract

A blue, aqueous solution of copper(II) sulfate is mixed with a red ethanolic solution of sudan III forming a purple solution. This mixture is extracted with a nonpolar solvent, resulting in the separation of the red and blue compounds. The nonpolar solvent may be kerosene, vegetable oil, mineral oil, or hexanes. Notes on handling are included.

Control of Chemical Equilibrium by Solvent: A Basis for Teaching Physical Chemistry of Solutions

“…A conformational equilibrium process can be expressed in general as conformer II conformer I (24) or for the special case of cis-trans isomerization as trans-isomer cis-isomer (25) The experimental approaches for determining conformer concentrations are not always sufficiently accurate (17); as a rule the difference in conformer energies is relatively small, ranging from 0.1 to 10-12 kJ͞mol. This is similar to the energies of dipole-dipole interaction and specific solvation in moderately active solvents, so it is difficult to discriminate between the conformer equilibrium and other processes.…”

Extraction Experiments Using Commercially Available Spices

“…The polarity of substances is a very abstract concept and students have a hard time understanding it unless a demonstration or a laboratory activity is given. There are laboratory activities that show the polarity of substances using the solubility of common substances like salt in various solvents, e.g., water to demonstrate the concept "like dissolves like" while other laboratory activities or demonstrations on polarity used colored compounds or colors extracted from plants [1][2][3].…”