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General
Check for the concentration of common acids and bases.
Suggested reading: Extraction, TLC, Recrystallization
Experiments
1. Step 2 (Work-up)
"36% HCl" refers to concentrated hydrochloric acid. There is nothing such as 100% HCl! See link above.
In some instances, the reaction turns green in color and a phase separation is observed upon standing. The experiment has to be repeated in such an event. Most likely, some of the methanol evaporated away, probably causing the phase separation. Keep in mind that the majority of the formaldehyde solution is water.
The extraction can be performed in one batch since the suspension after addition of the water does not fit entirely into the 125 mL separatory funnel. How much solvent is appropriate here to use for extraction? (Hint: see chapter about "Extraction Theory" in the Survival Kit Reader)
The organic layer should be extracted once with sodium bicarbonate solution and once with water before being treated with saturated sodium chloride solution and drying it over Na2SO4. This steps remove more of the unreacted formaldehyde from the organic layer and also provide an almost neutral pH-value.
The removal of the solvent should be aided by applying an air stream.
The recrystallization step requires a significant amount of time in some casess. The crude product is dissolved and then stored over night in a closed container. If the solution is too viscous, crystals generally form very slowly. The solution should not be placed in an ice-bath since there is a significant danger that the phenol precipitates as well.
The crude and the recrystallized product have to be examined by TLC in order to evaluate their composition and purity.
Independent if the product was a solid or an oil, an IR spectrum should be acquired to get more information.