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Solvent A is a pain, and tough to separate without distillation. It may even be tough to separate
with distillation as the components may form azeotrope with each other. the good news is that the odds are that the mixture will most likely be fine to use as is in place of just xylene, or just toluene.
Solvent B might as well form 3 layers, as it is predicted by the densities of each solvent if washed with water. DCM going to the bottom, methanol dissolving in the water in the middle and toluene floating atop. It may require to do this thing 3-4 times to wash them away thoroughly. Actually it would be nice to see if this solvent will behave as predicted.
Solvent C may again be similar to B. n-butanol does not readily dissolve in water, it floats atop of it. It is only slightly soluble in water, just like DCM. Again, it would be nice to see if 3 layers (n-butanol:top, water:middle and DCM:bottom) form if this solvents gets mixed with water.
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