A System of Qualitative Chemical Analysis (Paperback)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: Besides the above mentioned common metals, most of the rarer metals give characteristic colored microcosmic salt or borax beads: Oxydizing flame. Reducing flame. Uranium Yellowish green. Green. Vanadium....Colorless. Green. Molybdenum. Colorless Black. Tungsten Colorless. Blue. Niobium Colorless. Violet or blue; in presence of Titanium Colorless. Violet. [iron, red. Didymium... .Colorless. Violet. The microcosmic salt bead serves further for the detection of silica, SiO2. The bases of the silicates are wholly dissolved by the bead while the silica, if not in too small quantities, may be seen undissolved in the molten bead, as a diaphanous mass, or "silica skeleton": NaPO3 ] CaSi03 = SiO2 + NaCaPO4. IV. FLAME REACTIONS A siry1i quantity oi the substance in hand is moistened 7ith hydrochloric acid and introduced into the outer j'-lame of the Bunsen lamp. Many substances are -volatilized tn d.give to the flame a characteristic color. Sodium Yellow, colorless through cobalt glass. A crystal of potassium bichromate or a piece of naner coated with mercuric iodide appear white in the sodium light. Calcium Yellowish red. Strontium Carmine. Lithium Crimson. Potassium Violet. Barium Yellowish preen. Arsenic, antimony, lead and copper chloride.. Blue. Boric acid, phosphoric acid and their salts, moistened with sul- phuric acid Green. B. Examination in the Wet Way I. SOLUTION After the preliminary examination in the dry way, the substance under examination is brought into solution and according to the nature of the substance, grouped in one of the following classes: A. Oxides And Salts. a) A small quantity of the substance is tested as to its solubility in water. If the substance is completely soluble, or only in pa...