Kjeldahl flask

The Kjeldahl flask is a round-bottom flask with a long wide neck that is used in the determination of nitrogen by Kjeldahl’s method. Since the use of this method has declined over the years as better methods have been developed, Kjeldahl flasks are more of use in small digestion processes or as collectibles.

General

The Kjeldahl flask has the appearance of a round bottom flask with a single long neck but without a ground glass joint. It's similar in appearance to a volumetric flask or a long neck Florence flask. Kjeldahl flasks are made of borosilicate glass.

Availability

Kjeldahl flasks can be bought online from lab suppliers, or from eBay.

Uses

• Kjeldahl method for determination of total nitrogen in a sample
• Chemical digestion of compounds
• Glassware collecting

References

Relevant Sciencemadness threads

• Interesting test of how well you know your labware