American journal of pharmacy . edto avoid the separation of carbon in the tube, but without , the well-known method of wet combustion with a mixtureof chromic anhydride and sulphuric acid was attempted, a number 230 Gehemic Acid. ( . Ma>, 1897. of analyses beinsr made with no better success than before. Adescription of this latter method with apparatus is given here, sinceit has answered admirably in the analyses of various derivatives ofgelsemic acid. In the combination flask (Fto^, i) from lo to 20 grammes of chro-mic anhydride are introduced, followed by t
American journal of pharmacy . edto avoid the separation of carbon in the tube, but without , the well-known method of wet combustion with a mixtureof chromic anhydride and sulphuric acid was attempted, a number 230 Gehemic Acid. ( . Ma>, 1897. of analyses beinsr made with no better success than before. Adescription of this latter method with apparatus is given here, sinceit has answered admirably in the analyses of various derivatives ofgelsemic acid. In the combination flask (Fto^, i) from lo to 20 grammes of chro-mic anhydride are introduced, followed by the gelsemic acid whichhas been accurately weighed off in a small thin glass tube, this isplaced in a nearly upright position in the flask, in order to avoidcontact with the CrOg before the proper time. After securing allthe joints of the apparatus, a slow current of pure oxygen gas ispassed through the entire apparatus until practically all of the airhas been removed, after which the current is regulated to about 20 O ^. ?^w^ Fig. t. bubbles a minute, which is continued throughout the entire combus-tion, unless the reaction becomes violent, when the current shouldbe temporarily closed. By slightly shaking the flash the gelsemicacid is caused to spill out, and is distributed through the chromicoxide, then the concentrated sulphuric acid which is contained inthe separation funnel is allowed to trickle over the mixture veryslowly, regulating the flow according to the energy of the , when the reaction is over, sufficient acid is added to makea bulk of about 20 to 30 The flask and contents are then cau-tiously heated, increasing gradually till just short of boiling tem-perature, which is kept up for a period of fifteen to twenty gases given off pass up through a well-cooled condenser into atube which is filled with spun glass, well covered with lead peroxide, ^-Mayia!^^} Gelsemic Acid. 231 which serves to retain any sulphur dioxide which is ca
Size: 1113px × 2245px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookidamericanjournal69phi, booksubjectpharmacy
