Blowpipe flame

Ldt-fett, n. soldering paste, -flamme, /. blowpipe flame. -fiussigkeit,/. soldering fluid. 

Ldtrohr-flamme, /. blowpipe flame, -fluss, m. blowpipe flux. -gebl e, n. blast lamp, -kapelle, /. blowpipe cupel, -kohle, /. blowpipe charcoal, -lampe, /. blowpipe lamp, -probe,/, blowpipe teat, -priifgeratschaft,/. apparatiis for blowpipe testing, -reagens, n. blowpipe reagent, -versuch, m. blowpipe experiment or test. 

Stirring rods. These are made from glass rod 3-5 mm in diameter, cut into suitable lengths. Both ends should be rounded by heating in the Bunsen or blowpipe flame. The length of the stirring rod should be suitable for the size and the shape of the vessel for which it is employed, e.g. for use with a beaker provided with a spout, it should project 3-5 cm beyond the lip when in a resting position. 

The table should be placed so that direct sunlight does not fall on the blowpipe flame. If this can happen, there should be a blind to cut out the sunlight. It is difficult to work glass in a flame in sunlight because the flame is then so difficult to see and the temperature of the glass cannot be judged properly. 

W. N. Hartley 57 found the alkali chlorides in the oxyhydrogen blowpipe flame give lines of elements with a more or less continuous spectrum believed to be due to the respective metals. Lithium chloride, however, gives no continuous spectrum. G. P. Thomson studied the anode rays from lithium chloride and other alkali halides. 

An apparatus for the filtration of small to moderate quantities of crystals incorporates the so-called Willstatter filtration nail. The latter consists of a thin glass rod flattened at one end. It is readily constructed by heating the end of a short glass rod in the blowpipe flame and pressing vertically upon an asbestos board. The nail is fitted into small glass funnel it is covered by a circle of a filter paper cut with the aid of a cork borer of appropriate size. A filtration nail r r and funnel, capable of handling up to 1 g. of solid is depicted... 

Second Method. 60 gms. of potassium cyanide are heated in a large iron crucible over a large burner or blowpipe flame until it begins to fuse. 140 gms. of red lead, in small portions at a time, are added while the mixture is stirred with a rod. When the addition is complete and frothing has ceased the fused mass is poured on to an iron tray. When cold, the mass is separated from metallic lead, ground in a mortar, and digested with 200 c.cs. of cold water for an hour. The filtrate from this mixture is treated with 25 gms. of ammonium sulphate and evaporated in a basin to dryness on a water bath. The residue, ground finely and transferred to a flask, is boiled with three instalments of alcohol under reflux to dissolve the urea from the potassium sulphate. Each extract... 

A combustion tube 80—85 cms. long and similar to that used for the estimation of C and H is selected. A glass rod is sealed to one end and the tube is heated near this end in a blowpipe flame until the glass softens, when it is quickly drawn out and rounded as described on p. 42. When cold it is thoroughly washed out and dried. 

The outer crucible is now heated in a large Bunsen or blowpipe flame so that the outer portions attain a high temperature before the substance in the smaller crucible begins to decompose. The whole is finally raised to a red heat. The crucibles and contents are allowed to cool, then digested with water in a strong beaker. Dilute HN03 is cautiously added... 

While still moist the filter is placed in a platinum crucible and carefully incinerated and calcined at a dull red heat (not in a blowpipe flame), the crucible being inclined to facilitate access of the air. After being cooled in a desiccator, the crucible is weighed BaS04 x 0-7468 — KjS04. 

The precipitate is dissolved in a little hot dilute hydrochloric acid and the aluminium hydroxide reprecipitated with ammonium chloride and ammonia. The precipitate is allowed to settle, washed by decantation and then on the filter with slightly ammoniacal hot water. The weight ol oxide obtained after igniting in a platinum crucible in a blowpipe flame is multiplied by two and the result diminished by the quantity normally present in wine (0 -o 1-0 -04 gram A1,0-, per litre). The remainder is calculated as alum. 

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