. The Pharmaceutical era. on precipitate I I ff^\^ from silver nitrate yellow I I /r^y^^N^ silver arsenite, AgjAsOj, I l^^^SvA soluble in ammonia and in acids. Arsenates precipi- S^if X^ ^^. ^*^ from silver salts the if/ it/^T dark red silver arsenate. , with solubilities similar to the arsenite. PRACTICAL Place a small quantityof arsenous oxid on char-cqal and heat with the blowpipe. Xote all the there any odor evolved?Is there an incrustation onthe charcoal? Can it bedriven with the blow pipeflame? 2. Heat the middle portion of a narrow glass tubeabout 15 cil. lo
. The Pharmaceutical era. on precipitate I I ff^\^ from silver nitrate yellow I I /r^y^^N^ silver arsenite, AgjAsOj, I l^^^SvA soluble in ammonia and in acids. Arsenates precipi- S^if X^ ^^. ^*^ from silver salts the if/ it/^T dark red silver arsenate. , with solubilities similar to the arsenite. PRACTICAL Place a small quantityof arsenous oxid on char-cqal and heat with the blowpipe. Xote all the there any odor evolved?Is there an incrustation onthe charcoal? Can it bedriven with the blow pipeflame? 2. Heat the middle portion of a narrow glass tubeabout 15 cil. long until it softens and draw the two endsapart. The result will be two tubes, each with a closedpointed end. Dry one of the tubes thoroughly by heatingits entire length and introduce a mixie-re of equal por-tions of arsenous oxid and powdered charcoal, shakingcarefully to the bottom. Heat the narrow portion con-taining the powder. Xote whether an odor is evolvedfrom the lube aiul whether any deposit is formed on Fig .36.—Marsh Test forArsenic, December 9, 1897.] THE PHARMACEUTICAL ERA. 871 3. Heat ono enrt of a glass tube about 10 cM. long un-til the bore closes. While still hot blow in the open enduntil the hot portion expands into a small bulb. Dry thetube by heating throughout, and allow to cool. Make amixture of equal parts or arsenous oxid and dried andpowdered sodium acetate and introduce into the the mixture and note any odor which may beevolved. (The evolved vapors are poisonous, and shouldnot be inhaled.) 4. Place a mixture of equal parts of waliT and hydro-chloric acid in a test tube, add a strip of copper foil andheat. If the materials are free from arsenic the sur-face of the foil should grow brighter. Now add a fewdrops of solution of potassium or any other ar-senous solution and continue heating. Does the copperchange colorV 5. Remove the copper, dry thoroughly, introduce into aclean, dry test tube, and apply heat. Does a sublimate
Size: 1297px × 1927px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, booksubjectdrugs, booksubjectpharmacy, bookyear1
