This book is 109 pages in length (paperback version published by Dover Books).
This is a somewhat dated book containing suggestions for chemical demonstrations with a “doing magic” theme. Despite the plethora of you tube videos out there, it is refreshing to get a hold of a classic book that gives a compendium of these popular demonstrations.
Some of these are indeed very interesting and fun to do but may require some modifications. Some of the demonstrations given in this book make use of chemicals and chemical handling procedures and exposure that probably would not pass muster against our stricter regulations on the storage, handling, and use of chemicals. There are some very classic demonstrations that I am going to try and perhaps adopt but I am mostly keen on using chemicals that are household items and also do not require any special handling or waste disposal, easy and not expensive to acquire, and, of course, safe to use in a regular lecture classroom.
In the beginning of the book, the author recommends some tips on how to put on an effective, engaging, and enjoyable chemical magic show.
Although the description of each demonstration is brief, it is well-organized. For each demo, the author organizes the information into “Action” (what the audience will observe), “You Need” (the chemicals, glassware, and equipment), “Why” (a chemical explanation of how the “magic” works), “How” (directions on how to carry out the magic demonstration), and “Suggestions” (tips to make the demo more effective, alternate chemicals or steps, safety precautions, etc.). For many of the demonstrations, the author offers an illustration for the more complicated set-ups. The safety precautions are lacking, however, or perhaps not adapted to the current regulations.
Below are some of the demonstrations I might try doing in my class. (Note: these descriptions are copied verbatim from the book.)
DEMONSTRATION 1:
Patriotic Colors
Action: From a bottle you pour a liquid into each of three beakers standing on a demonstration table. You produce the colors red, white and blue.
You Need: Solution of alcohol containing phenolphthalein in the first beaker; concentrated lead nitrate in the second beaker; and concentrated copper sulfate in the third beaker. The bottle contains dilute ammonium hydroxide.
Why: The action of ammonium hydroxide with the reagents in the beakers produces color changes. In the first beaker, the color change is due to an indicator. Double displacement occurs in the second and a complex ion is formed in the third.
How: A few drops of reagent in each beaker is sufficient. The intensity of the color depends on the number of drops of reagent used. Suggestions: The demonstration has good audience response. It is quite foolproof, and effective with good lighting.
DEMONSTRATION 2:
Water to Milk to Water
Action: Three quart milk bottles are standing on the table. The first appears to be half full of water. The others appear to be empty. You pour the water from the first into the second, changing the water to milk, and the milk formed in the second is poured into the third bottle. Milk formed in the second appears to change to water in the third.
You Need: Distilled water to make up solutions. In the first bottle; solution of 1 gram calcium chloride in 500 ml. water. In the second bottle; solution of 0.2 gram ammonium oxalate in 10 ml. water. In the third bottle; 5 ml. concentrated sulfuric acid.
Why: White insoluble calcium oxalate is formed when the first solution is poured into the second. This precipitate dissolves on pouring it into the third bottle.
Suggestions: This demonstration can also be done by the use of calcium oxide, sodium carbonate and concentrated hydrochloric acid. Place one gram calcium oxide in 500 ml. of water. Stir and filter. This clear solution is placed in the first bottle. In the second bottle place 0.5 gram sodium carbonate in a little water. In the third you place a few mls. of concentrated hydrochloric acid. Pouring the clear limewater which is in the first bottle into the second results in a white precipitate of calcium carbonate. Pouring the contents of the second bottle into the third results in a clear solution since the solid material then dissolves. Milk can be made to appear to come from water by the use of barium chloride and concentrated sulfuric acid. Dissolve barium chloride in 500 ml. of water in the first bottle. Pour this clear solution into the second bottle containing the acid. An insoluble white precipitate forms which resembles milk.
DEMONSTRATION 3:
Fast Rusting
Action: A colored liquid rises in a long glass tube attached to an inverted liter flask filled with steel wool. In ten or fifteen minutes the liquid will ascend into the flask and continue to rise for an hour.
You Need: Steel wool; liter flask with one-hole rubber stopper and three feet of glass tubing; crystal of potassium permanganate; dilute hydrochloric acid.
Why: Oxygen, combining with iron in steel wool, produces partial vacuum in a flask.
How: Over a mass of steel wool about one liter in volume, pour dilute acid and rinse in tap water. Push this moist steel wool into a one-liter flask. To the flask attach three feet of glass tubing by means of the one-hole rubber stopper. Suspend the arrangement with the flask inverted on a high ring stand over a beaker containing water colored with the potassium permanganate.
Suggestions: The acid is used to remove rust from the steel wool. The metal with its great surface is oxidized removing oxygen from the air in the flask, resulting in a partial vacuum. This causes the liquid to rise. The acid treatment should be done shortly before the demonstration since the steel wool oxidizes rapidly after cleaning.
DEMONSTRATION 4:
Wonder Picture
Action: You decide to paint a picture of someone in the audience so you take a sheet of drawing paper and proceed to paint the face of a person. You have two paint pots with a brush in each. The face is painted with one brush and the hair with another. The picture is faint pink and you proceed to warm it over a flame. The face becomes a deep bluish green and the hair a deep violet.
You Need: A few crystals of hydrated cobaltous chloride dissolved in water in the first paint pot and a few crystals of hydrated cobaltous acetate dissolved in water in the second paint pot.
DEMONSTRATION 5:
Acid Breath
Action: You blow your breath through a straw into a beaker of pink liquid. The liquid turns colorless in a minute or so.
You Need: Soft drink straw; 250 ml. beaker, half filled with water; 2 to 3 drops phenolphthalein solution; one drop 6 molar sodium hydroxide.
Why: Carbon dioxide from the breath dissolves in the basic solution, neutralizing it, and turns the indicator colorless.
How: Add the indicator and the sodium hydroxide to the water and stir. This forms a basic solution which turns the indicator faint pink.
Suggestion: Do not use too much sodium hydroxide or the carbon dioxide will not be able to neutralize the base and the color will not change.
DEMONSTRATION 6:
Educated Moth Balls
Action: Little white balls rise and fall in a tall cylinder while spectators are trying to guess the reason for the fascinating motion.
You Need: Ten grams marble chips; five grams ordinary salt; dilute hydrochloric acid; moth balls; tall cylinder or beaker; food coloring.
Why: Carbon dioxide gas accumulates on each moth ball. In time the gas bubbles will have sufficient buoyancy to lift the moth ball to the surface. Loss of gas at the surface causes the moth balls to sink. This movement continues for hours or days.
DEMONSTRATION 7:
Oxygen in Air
Action: An empty inverted water glass rests on a dish of water. Over a period of several hours water rises in the glass and eventually occupies one-fifth of its volume.
You Need: Small wad of steel wool; vinegar.
Why: To show that air is one-fifth oxygen. How: Pour vinegar over the steel wool and wedge it into the base of the water glass. Invert over the dish containing water. Rusting of the iron slowly removes the oxygen as the water level rises. A similar, more striking experiment is the one entitled “Fast Rusting.”
DEMONSTRATION 8:
Boiling Water in Paper
Action: Water is heated to the boiling point in a box-like paper container placed on a screen. The screen supported by a ring stand is above a Bunsen burner.
You Need: Sheet of typewriter paper; four paper clips or Scotch tape; ring stand; ring; screen.
Why: Conduction of heat through the paper is seen to increase the temperature of water to the boiling point.
How: Fold typewriter (or stronger) paper about two inches inward from four directions and fasten the ends together with paper clips or Scotch tape. The base of this box-like container will be about 6 × 4 inches. Pour in about 200 ml. of water.
Suggestions: An interesting variation of the experiment is to boil water in a paper bag. Water in contact with the paper absorbs the heat, keeping the temperature low enough to prevent combustion of the paper. Water is heated slowly in these experiments since paper is a very poor conductor of heat.
DEMONSTRATION 9:
Cold Boiling
Action: A flask of water is boiling on a ring stand mount. The flask is removed, quickly stoppered, and placed under a cold water tap. The water in the flask continues to boil furiously for several minutes.
You Need: One liter spherical flask (Pyrex); ring stand and clamp; rubber stopper.
Why: When boiling the flask is full of steam which rapidly condenses under cold water. At reduced pressure the water will boil at lower temperature.
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