Organic Chemistry Laboratory Survival Manual

Distillation Part 2 (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Pressure and Temperature Corrections You’ve found all the leaks and the pressure in your vacuum distillation setup is, say, 25 torr. Now you need to know the boiling point of your compound, 1-octanol, this time at 25 torr and not 760 torr. You realize it’ll boil at […]

Distillation Part 3 (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu CLASS 3: FRACTIONAL DISTILLATION For separation of liquids, soluble in each other, that boil less than 25 °C from each other, use fractional distillation. This is like simple distillation with the changes shown (Fig. 80). Fractional distillation is used when the components to be separated boil within […]

Reflux (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Just about 80% of the reactions in organic lab involve a step called refluxing. You use a reaction solvent to keep materials dissolved and at a constant temperature by boiling the solvent, condensing it, and returning it to the flask. For example, say you have to heat […]

Sublimation (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Sublimation occurs when you heat a solid and it turns directly into a vapor. It does not pass GO nor does it turn into a liquid. If you reverse the process — cool the vapor so that it turns back into a solid—you’ve condensed the vapor. Use […]

Chromatography: Some Generalities (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Chromatography is perhaps the most useful means of separating compounds to purify and identify them. Indeed, separations of colored compounds on paper strips gave the technique its colorful name. Though there are many different types of chromatography, there are tremendously striking similarities among all the forms. Thin-layer, […]

Thin-Layer Chromatography: TLC (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Thin-layer chromatography (TLC) is used for identifying compounds and determining their purity. The most common adsorbent used is silica gel. Alumina is gaining popularity, with good reason. Compounds should separate the same on an alumina plate as on an alumina column, and column chromatography using alumina is […]

Wet-Column Chromatography (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu This is, as you may have guessed, chromatography carried out on a column of adsorbent, rather than a layer. Not only is it cheap, easy, and carried out at room temperature but you can separate large amounts, gram quantities, of mixtures. In column chromatography, the adsorbent is […]

Dry-Column Chromatography (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Dry-column chromatography is another approach to the separation of large quantities of a mixture of products. I think it’s easier than wet-column chromatography, though more limited. 1. Weigh about 80 g of the adsorbant (alumina, silica gel, etc.) for a typical 15 X %-in. column, into either […]

Refractometry (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu When light travels from one medium to another it changes velocity and direction a bit. If you’ve ever looked at a spoon in a glass of water, the image of the spoon in water is displaced a bit from the image of the spoon in air, and […]

Instrumentation in the Lab (Laboratory Manual)

  By : James W Zubrick Email: j.zubrick@hvcc.edu Electronic instrumentation is becoming more and more common in the organic lab, which is both good and bad. The good part is that you’ll be able to analyze your products, or unknowns, much faster, and potentially with more accuracy than ever. The bad part is that you […]

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