482 PRACTICAL ORGANIC CHEMISTRY Substances suitable for the estimation: acetanilide, sucrose, glucose, cinnamic acid, diphenylamine, salicylic acid, vanillin, />-bromoacetanilide, toluene p-sulphonamide. Estimation of Nitrogen. The two chief methods for estimating nitrogen in organic compounds are (i) the Dumas method, which can be applied to all organic com-pounds; (ii) the Kjeldahl method, which is of more restricted applica-tion, but which is frequently used in biochemical and physiological work. Its limitations are indicated in the description of the method (P- 492). The Dumas Method. Principle. A definite amount of the substance (ca. 25 mg.) is weighed out, transferred to a combustion tube and is burnt with a Bunsen flame in an atmo-sphere of air-free carbon dioxide, an oxidising filling (cupric oxide) of the tube being used as a source of oxygen. The carbon present is converted to carbon dioxide, the hydrogen to water, any sulphur to sulphur dioxide, and nitrogen and halogens are evolved in the free state. This resulting nitrogen is swept out of
This is the end of the preview. Sign up
access the rest of the document.
This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.