| Kjeldahl apparatus | <apparatus, chemistry> An apparatus for distilling ammonia arising from acid decomposition of an organic compound; used in nitrogen analysis. (05 Mar 2000) |
|---|---|
| Kjeldahl method | More specifically see: macro-Kjeldahl method, micro-Kjeldahl method. (05 Mar 2000) |
| Kjeldahl, Johan | <person> Danish chemist, 1849-1900. See: Kjeldahl apparatus, Kjeldahl method, macro-Kjeldahl method, micro-Kjeldahl method. (05 Mar 2000) |
| macro-Kjeldahl method | A procedure for analyzing the content of nitrogenous compounds in urine, serum, or other specimens, usually to determine relatively large amounts of nitrogen (e.g., 20 to 100 mg); the specimen is treated with a digestion mixture (copper sulfate and sulfuric acid), heated thoroughly, and made alkaline with a solution of sodium hydroxide; ammonia is then distilled from the mixture, trapped in a boric acid-indicator solution, and titrated with standard hydrochloric or sulfuric acid. (05 Mar 2000) |
|---|---|
| micro-Kjeldahl method | A modification of the macro-Kjeldahl method designed for the analysis of nitrogenous compounds in relatively small quantities, e.g., specimens in which the total content of nitrogen is in the range of 1 to a few mg. (05 Mar 2000) |