Actions of dilute hydric sulphate- On iron, 27; zinc, 28; ferrous sulphide, 28 On calcic carbonate, 29; manganic binoxide, 30 On silver, 30; mercury, 31; copper, 32; hydric chloride, 33; ferrous sulphate, 33 Potash on hydric sulphate, 35; h. chloride, 36; Soda on hydric sulphate, h. chloride, h. nitrate, 36 [Preparation of ammonia gas, 37] Ammonia on hydric sulphate, h. chloride, h. nitrate, Ammonia gas on hydric chloride gas, 38 [Action of heat on ammonic nitrate, 38] Action of alkaline carbonates on acids, 39 Oxides of metals, 52; of non-metals, 55 Salts. Sulphides, 56; hyposulphite, 57; sulphates, 57; chlorides, 59; chlorate, 60; bromides, 60; iodides, 60; fluorides, 61; carbonates, 61; nitrates, 62; phosphates, 63; silicates, 64; borates, 64; REAGENTS. Dry reagents, 68; test papers, 68; wet ANALYSIS OF SINGLE SUBSTANCES- A PRIMER OF CHEMISTRY. EXPERIMENTS WITH SOME OF THE ELEMENTS. The Pneumatic Trough.-This is an instrument used in the collection of gases (pneuma, Greek for gas). The ordinary form consists of two parts made of earthenware, a pan and a so-called beehive shelf. To see how it is used, fill a bottle with air from the lungs by its means. Put some water in the trough, so as to rise about half an inch above the top of the shelf, take a bottle, lay it down in the water, and when it is full or nearly full, raise it cautiously on to the shelf, with the mouth downwards and over the top hole, allowing no water to escape. Now place one end of a long glass tube through the side hole of the shelf, and blow through the other end. The air will rise, and gradually take the place of the water in the bottle. The Hydrogen Apparatus. This consists of a narrow-mouthed bottle, fitted with a cork, through which passes a bent glass tube, the exit of the latter being joined with a long glass tube by means of a piece of india-rubber tube. To Cut and Bend the Glass Tube.-Take a piece of soft tubing (soft = easily softened by heat), if one B end is not even scratch it with a triangular file a short distance from the end and then break it. Make a scratch about five inches from the end, and break the piece off. Hold the piece in an ordinary gas flame, turning it slowly round till the middle is soft, then take it away from the flame and bend it at right angles. Remove the sharp edges at each end with a file. To Prepare and Bore the Cork.-Select a cork apparently larger than necessary to fit the bottle, wrap the cork in paper to keep it clean, and roll it under your foot to soften it. It will now probably fit the bottle tightly. Heat the point of a rat-tail rasp red hot, bore the cork through the middle, and then enlarge the hole carefully so that the glass tube, after slight warming at the end, will just fit into it. HYDROGEN. Preparation. Put some zinc into the bottle, fill it a third with water, and add hydric sulphate (sulphuric acid) to the extent of a fifth the volume of the water. If no effervescence occurs, the zinc is too pure, and two drops of platinic chloride solution, or a little cupric sulphate solution, must be added. Insert the cork with tube, allow the air to be expelled from the bottle, and then begin to collect the gas over the pneumatic trough. When the receiving bottle is full, close its mouth under water with a saucer or similar vessel, remove it from the trough, and set it mouth downwards on the table, the mouth being closed by the water in the saucer. Burns in Air.-Raise the bottle, still keeping it inverted, apply a light immediately, turn the mouth upwards and pour in water without delay |