Frederick Hutton Getman

“ We are not authorized to infer the pre-existence of ammonium, however, from the [Pg 35] appearance of this reaction, for the presence of nitrogenous organic matter in the substance, which would be decomposed by this treatment, would give rise to such a reaction.
18. Potassium.—Potassium is recognized by the color which its salts impart to the Bunsen flame. If a portion of a salt of potassium be held on a platinum wire in the flame, it imparts a blue-violet tint which rapidly disappears.
19. Sodium.—Like potassium, this alkali metal is detected by the color which its salts give to the flame. ”

“ Some analysts prefer to make a small loop in the end of the wire before taking up the borax to make the bead. Care should be taken to see that the bead is colorless before bringing it in contact with the substance.
As the depth of color produced is largely dependent upon the amount of substance taken, some little caution should be exercised to insure taking up about the same quantity each time. ”

“ Illustrations. Make several beads, and [Pg 20] note the colors characteristic of the following oxides: cobalt, nickel, iron, manganese, chromium, and copper.
The microcosmic salt bead dissolves almost every oxide except silica, SiO2, and this is seen to float about in the melted mass. This is used as a test for silica. ”

“ Color, pale copper-red. Lustre, metallic. Very brittle. Heated in an ignition tube yields a copious sublimate of arsenious oxide, the residue falling to a greenish powder. Before the Bp. on Ch. fuses to a white brittle globule emitting arsenical fumes. In borax bead gives color characteristic of nickel. Frequently in this mineral a portion of the arsenic is replaced by antimony.
Ores of Silver
Native Silver, Ag.—
H = 2.5-3.0, G = 10.1-11.0. ”

“ To detect the presence of this hypothetical metal, mix the assay with about four parts of Na2CO3, place in an ignition tube, and apply heat. The odor of the evolved gas will be recognized, and if a piece of red litmus paper be moistened and held at the mouth of the tube, it will be turned blue by the escaping ammonia gas. ”

“ A very small, shallow hole should be cut in the Ch. to receive the assay. The Bp. flame should be directed at an angle of about 30° with the surface of the Ch. Considerable care must be taken lest the hole in [Pg 11] the Ch. is burned too deep and the assay lost in the coal.
The force of the air from the jet must also be borne in mind for a strong blast, or sudden puffs may blow the substance away.
The following changes are to be looked for:—
a. Whether the substance is volatile or non-volatile.
Illustrations. Examine before the Bp. on Ch. some arsenious oxide, As2O3, also some alumina, Al2O3. ”

“ Intumescence is the swelling of the substance upon heating. [Pg 10]
Decrepitation is the crackling of a substance due to the sudden expansion of combined water upon heating.
Deflagration is the burning of a substance with explosive violence, generally due to excess of oxygen.
Incandescence is the white light emitted by a substance that is infusible when subjected to a high temperature.
Examination on Charcoal alone.—The size of the assay should be about that of a mustard seed. ”

“ Since the advance of organic chemistry in this country must, in a measure, depend on the nature of the available text-books, both the author and the translator deserve our thanks for providing us with a work such as the present one. ”

“ CHAPTER II GENERAL OUTLINE OF BLOWPIPE ANALYSIS
[ABBREVIATIONS: O. F. for oxidizing flame, R. F. for reducing flame, Ch. for charcoal, Ct. for coating, Bp. for blowpipe.]
In order to examine a substance before the blowpipe to determine the presence or absence of certain elements, it becomes necessary to arrange a systematic method. As with all branches of chemical work, one's success is largely dependent upon neatness of manipulation and carefulness of observation.
The following order of observation is essentially that given by Berzelius:—
1. ”