SIMPLE CHEMICAL EXPERIMENTS SIMPLE CHEMICAL EXPERIMENTS By ALFRED MORGAN Illustrated by THE AUTHOR APPLETON-CENTURY-CROFTS, INC. NEW YORK COPYRIGHT, 1941, BY D. APPLETON-CENTURY COMPANY, INC All rights reserved. This book, or parts thereof, must not be reproduced in any form without permission of the publisher. PRINTED IN THE UNITED STATES OF AMERICA CONTENTS CHAPTER PAGE I. YOUR LABORATORY i II. EXPERIMENTS WITH PRECIPITATES .... 26 III. EXPERIMENTS WITH SULFUR AND SOME OF ITS COMPOUNDS 54 IV. EXPERIMENTS WITH OXYGEN AND OXYGEN COM­ POUNDS 73 V. EXPERIMENTS WITH GASES AND SOME OF THEIR COMPOUNDS 103 VI. CHEMICAL TESTS 123 VII. SAFE "FIREWORKS" 144 VIII. EXPERIMENTS WITH A FEW ORGANIC COMPOUNDS 156 IX. CHEMICAL TRICKS AND MAGIC 170 X. MISCELLANEOUS EXPERIMENTS 186 XI. PRACTICAL USES FOR YOUR CHEMICAL KNOWL­ EDGE 214 XII. THE CHEMICALS YOU WILL NEED . .231 INDEX OF CHEMICALS 259 GENERAL INDEX 263 V SIMPLE CHEMICAL EXPERIMENTS *> CHAPTER I I YOUR LABORATORY I OST of the experiments described in this book can be M performed without elaborate equipment or apparatus. | For them you will need only a few bottles, test-tubes, meas- i uring-spoons, and an alcohol lamp. Jelly glasses, mayonnaise f jars, small enameled saucepans, and thin glass tumblers can | often be substituted for the beakers, flasks, and glassware of I the professional chemist. t A few of the experiments require beakers, flasks, tubing, | funnels, filter paper, crucibles, mortar and pestle, and Bunsen I burner. The small sizes of these are not expensive. Frequently the cost of apparatus and chemicals can be shared by estab­ lishing a "community" laboratory which is used by two or more experimenters. Of course it is more convenient to use commercial chemical equipment and more "professional" than to use the home- l made variety. Several firms which advertise in the columns of the popular * mechanical and scientific magazines will fill mail orders for J glassware and other apparatus. Four or five dollars will equip I a home "lab" well. 2 SIMPLE CHEMICAL EXPERIMENTS THE LABORATORY BENCH For occasional experimenting, the kitchen table makes a good place. But the experimenter who devotes a good deal of time to his hobby or who owns a considerable assortment of chemicals and apparatus needs a table or bench where he can leave his equipment and where it will remain undisturbed. A design for a simple laboratory bench which can be built from packing- case lumber. A hammer and saw are the only tools required. YOUR LABORATORY 3 ^ A table, a shelf, and a bucket or large can for waste mate- i rial are the essentials in arranging a home laboratory. When I there is a choice of locations, the spot selected should be one * where there is no danger to rugs and furniture. If possible, I it should be near running water, a gas outlet, and a sink. ^ An old kitchen table, a home-made table, even a large I packing-case, when fitted with shelves, is a satisfactory lab­ oratory bench. Here much that is interesting about one of the most important and most useful of modern sciences may be learned. A coat of asphaltum paint will protect the surface of the table and make it resistant to water, acid, and other chemicals which may boil over or be spilled during an ex­ periment. Cover that portion of the bench where the Bunsen burner or alcohol lamp is used with sheet-asbestos. A SIPHON BOTTLE When running water is not available, a siphon bottle for storing and delivering water at the laboratory bench will be found useful. This can be rigged out of a one-gallon glass jug, a funnel, rubber tubing, a two-hole stopper, glass tubing, and a spring clothes-pin or pinch-cock. The whole arrangement is shown in the illustration. The siphon bottle should be set on a shelf or bracket above the bench level. To start the siphon, fill the bottle by pouring water in the funnel. Then tilt the bottle until the water fills the glass tube and begins to flow out of the rubber tube. Clamp the spring clothes-pin or pinch-cock over the rubber tube so as to shut off the flow of water and set the bottle on its shelf above the level of the "lab" bench. After the siphon has been started, water will flow out of the rubber outlet tube when- SIMPLE CHEMICAL EXPERIMENTS SIPHON BOTTLE The amateur chemist who does not have running water near his labora­ tory table should rig up a siphon bottle. A glass funnel (i) and a bent glass tube (4) are inserted in a 2-hole cork (2) which fits into a 1-gallon glass jug (3). The end of the tube inside the jug should reach almost to the bottom. A rubber tube (5) is fitted to the outside end of the glass tube. It should hang down below the bottom of the jug and be fitted with a pinch-cock or spring clothes-pin (6) which will clamp it shut. Fill the jug and tube with water and place it on a shelf (7) at the back of the laboratory table. Water may be drawn from the jug by releasing the clothes-pin or pinch-cock. ever the pressure of the spring clothes-pin is removed, unless the bottle is empty. The water in the bottle can be replen­ ished by pouring water into the funnel. BOTTLES Empty bottles of all sizes and shapes are needed in the home laboratory. Some will be useful for storing and pre- YOUR LABORATORY 5 serving your chemicals. Others can be used as part of your laboratory apparatus. Small, wide-mouthed bottles and small jars can be used for storing powdered or crystallized chemi­ cals, test papers, etc. The ordinary narrow-necked or small- mouthed bottle will serve best for liquids. BOTTLES OF ALL SIZES ARE USEFUL IN THE HOME LABORATORY Wide-mouthed bottles make the best containers for powders and crystals. Liquids and solutions can be poured most easily from narrow-necked bottles. Acids and solutions of strong alkalis (sodium hydroxide, ammonium hydroxide, etc.) should be kept in bottles provided with rubber or glass stoppers. Old bottles must be thoroughly washed, rinsed, and dried before using. A bottle brush will assist greatly in the cleansing process. Bottles in which acids are stored should have glass or rubber stoppers. Sulfuric, nitric, and hydrochloric acids will soon decompose a vegetable cork. 6 SIMPLE CHEMICAL EXPERIMENTS LABELING BOTTLES AND JARS All bottles and jars containing chemicals should be labeled With the name of the contents and, if you wish, with the chemical formula for same. This is a good way to become familiar with the formulas that chemists use. A formula indi­ cates a single molecule of a compound. It shows at a glance just what the elements of a compound are and how they combine. This is a simple method of preparing a bottle or other piece of glass­ ware so that you can write on it with a pencil. The surface of the glass is roughened or frosted by rubbing with a Carborundum stone kept wet with water. The pencil marks can be rubbed off with a damp cloth. A bottle is easily labeled with a strip of paper upon which the name and formula for its contents are written. The label can be held in place and at the same time protected from stains with a piece of transparent "Scotch" cellulose tape. A strip of adhesive bandage will adhere firmly to clean YOUR LABORATORY 7 glass and may be used as a label. Stick it on the glass and then write on the name with pen and ink. You can write or print directly on glass with a pencil or crayon if you first roughen or frost the surface with a Car­ borundum stone. The label may be erased by scrubbing with a piece of soft rubber. CORKS AND STOPPERS Corks and rubber stoppers are a necessity to the chemist. They can be purchased in all sizes at drug-stores and chemi­ cal-supply houses. You can buy some sizes at the "dime" store. Several firms dealing in laboratory supplies sell an assortment of 150 corks containing 15 different sizes for 75 cents. Rubber stoppers in small quantities vary in price from 1 to 10 cents each, depending upon the size. SET OF CORK BORERS HOME-MADE CORK BORER The only way to make a satisfactory hole in either a vegetable or rubber cork is to do it with a cork borer Cork borers are metal tubes with sharp cutting edges The sketch at the left is a set of three factory-made cork borers The sketch at the right shows how to make cork borers by beveling the end of a brass tube with a file and providing a handle. CORK BORERS In order to perform some experiments, corks provided with one or two holes are necessary. When a set of cork borers is 8 SIMPLE CHEMICAL EXPERIMENTS not handy, holes can be made with a red-hot nail. But the best method of boring a hole in a cork is to use a cork borer made just for that purpose. These can be used to make holes in rubber stoppers also. A set of six borers costs about 65 cents. You can make your own out of some thin-walled brass or metal tubes by sharp­ ening one end. File or grind one end to a bevel so as to form a sharp cutting edge. Drill the opposite end so that a nail can be slipped through to form a handle.