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absorbed action added ammonia antimony appears arsenic arsenious acid atom become bismuth boiling bottle calcium called carbonic acid charcoal chemical chlorhydric acid chlorine closed cold collected color combination common composition compounds condition contains converted cooled copper crystals decomposed deposited dilute dissolved distilled elements employed example experiment fact fire flame flask follows formed formula gases glass grms heat hydrate hydrogen iodine iron known lead less light liquid matter means melted mercury metal method mixed mixture nitrate nitric acid nitrogen obtained occurs ordinary oxide oxygen ozone pass phosphoric acid phosphorus piece portion potassium powder precipitate prepared present produced properties proportion pure quantity reaction readily remains removed salt silver slowly sodium solid soluble solution specific gravity strong substance sulphide sulphuric acid temperature tion tube unites vapor volatile volume weight
Página 66 - ... volumes of nitrogen combining chemically either with one, two, three, four, or five volumes of oxygen, and with no other proportions whatsoever. As for volumes, so for weights ; the proportional weight of oxygen in these oxides rises by definite leaps from the first member of the series to the last. This definite, step by step mode of forming chemical compounds is one of the most characteristic, as it is one of the most general facts of chemistry ; no other science offers a parallel to it; but...
Página xix - XXVI, adapted expressly for holding funnels, are very convenient and not expensive. In general, care should be taken that the lower end of the funnel touch the side or edge of the vessel into which the filtrate descends, in order that the liquid may not fall in drops, but run quietly down without splashing. Sometimes there is no objection to thrusting a funnel directly into the neck of a bottle or flask, but in this case an ample exit for the air in the bottle must be provided (Fig.
Página 52 - ... coarse sand. Imbed the bottom of the retort in sand, contained in a small iron pan placed over the gas-lamp on a ring of the iron-stand. Thrust the neck of the retort into the receiver with two tubulatures ; the retort-neck should fit the tubulature of the receiver with tolerable accuracy. The second tubulature of the receiver should be left open, or loosely covered with a bit of glass, in order to avoid the possibility of any pressure being created within the retort during the operation. Place...
Página 210 - Ordinary phosphorus, when perfectly pure, is a transparent, colorless, wax-like solid of 1*8 specific gravity, which, when freshly cut, emits an odor like garlic, though under ordinary conditions this odor is overpowered by the odor of ozone, which, as has been previously stated (§ 164), is developed when phosphorus is exposed to the air. It unites with oxygen readily, even at the ordinary temperature of the air, and with great energy at somewhat higher temperatures (above 60°) ; when in contact...
Página 607 - Small cylinders or bells only can be used ; and the well of the trough should be scooped out but a little larger than the bell or cylinder selected, with its principal dimension horizontal, and its bottom curved to fit the cylindrical bell which is to be laid in it : the shelf, too, should have but a small area, sufficient only for four or five bells of 3 or 4 cm. diameter. In using a pneumatic trough, of any construction or dimensions, the student should be on his guard against two difficulties...
Página 100 - NaaS0, produced. In each case the sum of the weights of the materials employed is, of course, equal to the sum of the weights of the products. If the questions suggest themselves — how much water will these 62-39 k. of chlorhydric acid gas saturate, and what will be the bulk of the concentrated solution so obtained ? — the answers can be easily deduced from the following data : — The strongest...
Página 451 - Place in the blue solution two or three copper cents, and leave the flask at rest for some days in a warm place. Then collect the little plates of pure silver, which have separated from the solution, upon a filter, and wash them, first with water, and then with ammonia-water, until the ammonia-water no longer shows any tinge of blue. This silver, washed finally with water and dried, is well nigh pure; twothirds of it may be again dissolved in nitric acid; the solution will contain pure nitrate of...
Página 434 - Mixtures of chlorate of potassium and organic matter are liable to explode, if strongly rubbed or but lightly struck. Wrap the mixture in a paper cylinder, and place the cylinder on a brick in a strong draught of air ; let fall upon the mixture a drop of sulphuric acid from the end of a glass rod ; a very vivid combustion will ensue, with the violet-colored flame characteristic of potassium.
Página 283 - Basic salts of bismuth are also known, in which a larger proportion of bismuth is present. Some of the normal salts crystallize well from acid solutions, but they cannot exist in solution unless an excess of acid is present. On diluting solutions of the normal salts with water, insoluble basic salts are precipitated ; this reaction recalls the behavior of antimony solutions. The nitrate of bismuth, Bi.,3(N,O,) + 9H.iO, is the commonest soluble salt of bismuth ; it is procured by dissolving the metal...
Página 600 - This practice is almost essential in periodical publications to which writer* of different theoretical views contribute. 715. In the midst of the doubts and discussions which to-day envelope chemical theories, the student will do well to remember that all these questions lie without the sphere of fact. They do not affect the actual composition or properties of a single element or compound ; they are questions of interpretation, classification, and definition. The existence of atoms is itself an hypothesis,...