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. Some of the more clearly not-so-safe demos to do in a classroom that sound spectacular but interesting at best:
- make use of “exotic” but intriguing chemicals such as white phosphorus, mercury, 400 mL benzene, and 590 mL of carbon tetrachloride(!). For instance, in reference to handling phosphorus dissolved in carbon disulfide, extreme care is advised as “a drop of this liquid will readily cause combustible materials to start burning”.
- produce phosphine (highly poisonous!) or 4-5 feet of an ammonia fountain or even carbon monoxide
- generate large violent explosive combustions from burning 25 mL of ether
- grinding glass until powder in form and allowing it to slowly dissolve in water
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:
- If a demonstration will create a lot of fumes, do it at the end of the show so that spectators can leave the room.
- Practice, practice, practice
- Color liquids with food coloring
- “To be entertaining as a performer of chemical magic, you must be a good storyteller”.
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.
DEMONSTRATION 10:
Blue Flare
Action: A few drops of water from a medicine dropper fall on a small mound of powder. An instantaneous blue flare is accompanied by smoke.
You Need: Four grams powdered ammonium nitrate; one gram powdered ammonium chloride; zinc dust.
Why: The catalytic effect of water is shown on a mixture of oxidizing and reducing agents.
How: SEPARATELY grind the chemicals in a mortar. Mix the ammonium nitrate and ammonium chloride and place in a mound on a metal sheet. Sprinkle with zinc dust. You are now ready for the reaction with water.
DEMONSTRATION 11:
DEMONSTRATION 11:
Burning Sugar Lump
Action: You challenge members of the audience to light a sugar lump with a match. You pass out sugar lumps and matches. No one is able to make a sugar lump burn. It merely melts when fire from the match comes in contact with it. You ask one of the spectators to pass a sugar lump back to you. When you set fire to the sugar lump with fire from a match, it burns with a flame.
You Need: Sugar lumps; matches; cigarette ashes.
Why: Cigarette ashes act as a catalyst in causing the sugar to burn.
How: On receiving the sugar lump from a spectator you push it against cigarette ashes which you have in your hand, or lying on the table. You light the sugar lump at the point of contact between the ashes and the sugar. It catches fire and burns at this point.
DEMONSTRATION 12:
Flare
Action: One drop of water from a medicine dropper falls on a small cone of powder. An instantaneous bright flare and smoke are followed by a glowing mass that persists for a couple of minutes.
You Need: Five grams powdered aluminum; 0.5 gram sodium peroxide.
Why: High temperatures accompany oxidation of aluminum by peroxide.
How: On a metal mat place a cone of the powdered aluminum to a height of 0.5 inch. Sprinkle the sodium peroxide loosely over the metal and mix it slightly into the metal.
Suggestions and CAUTIONS: Addition of a drop of water to the sodium peroxide generates oxygen. The heat of reaction is great enough to cause the powdered aluminum to burn with an intense flame which is blinding to the eye. After the initial flare the metal continues to glow. Sodium peroxide is somewhat difficult to handle and materials after the combustion should be flushed down the sink. Great care must be taken to guard against burns since the reaction is rapid, the heat intense and the products corrosive.
DEMONSTRATION 13: (use saturated solution of salts instead and over flame)
Fireworks
Action: On the demonstration table are small piles of powder into which has been placed a thin taper of paper. Ignition of the paper will in turn cause the powder to flare up with the colors ordinarily seen in fireworks.
You Need: A mixture of chemicals, each ingredient in powder form, mixed in the ratios indicated.
BLUE FIRE potassium chlorate 8 copper sulfide 2 sulfur 4 mercurous chloride 2 copper oxide 1 charcoal 1 GREEN FIRE barium nitrate 12 potassium chlorate 3 sulfur 2
WHITE FIRE potassium nitrate 7 antimony sulfide 1 sulfur 1
RED FIRE strontium nitrate 4 potassium chlorate 4 charcoal 2 sulfur 1
YELLOW FIRE potassiuim chlorate 6 sodium oxalate 2 charcoal 2 sulfur 1
PURPLE FIRE copper sulfate 1 sulfur 1 potassium chlorate 1
How: Each substance should be ground to a powder separately in a mortar, dried, then placed on a large sheet of paper in the ratios indicated. The mixing is done by rocking the paper back and forth. The small pile of mixed powder is placed on a metal mat for ignition. Ignite by placing a thin piece of filter paper in the pile and lighting it with a match. To make the filter paper sensitive soak it first in a concentrated solution of potassium nitrate. Then allow it to dry.
DEMONSTRATION 14:
Fire Writing
Action: You touch the lighted end of a cigarette to one side of a sheet of paper. The word “Welcome” is gradually spelled out in fire across the paper. The paper is consumed only at the point of burning.
You Need: Ten grams potassium nitrate in 25 ml. water; small paint brush; fairly heavy paper that is somewhat absorbent.
Why: Burning paper is oxidized by potassium nitrate.
How: Paint the word on the paper with the saturated potassium nitrate solution. You should go over the word more than once to get enough of the salt in contact with it. Be certain that all the letters are connected or the fire will go out. The paper must be dry when lighted. Mimeograph paper seems to work well.
Suggestions: You may wish to burn out other words than the one suggested or you may wish to draw out pictures of animals or other objects. The experiment is easy to perform and shows off best in the dark.
DEMONSTRATION 15:
Delayed Fire
Action: Several drops of liquid from a medicine dropper fall into a paper cup placed over a metal mat. After several seconds a reaction takes place with a burst of flames.
You Need: One gram pulverized potassium permanganate; glycerine in a small dropper bottle; paper cup; metal mat.
Why: Pulverized potassium permanganate oxidizes glycerine rapidly. Heat generated results in a flame.
How: Place the paper cup containing the potassium permanganate on a mat. Glycerine is then dropped into the cup.
Suggestions: You may use an iron crucible in place of a paper cup. If the crucible has been warmed previously, an immediate reaction takes place. Otherwise, a period of up to a minute will elapse before the flame occurs. This experiment is most effective in a darkened room.
DEMONSTRATION 16:
Rat Nest
Action: The demonstrator drinks water from a glass. He decides to sprinkle some of it on a “rat nest” with a medicine dropper. Immediately the rat nest bursts into a vigorous flame and burns despite the water on it.
You Need: One gram sodium peroxide; excelsior (tinder or wood shavings); evaporating dish; medicine dropper.
Why: Oxygen is formed when water reacts with sodium peroxide. Heat that accompanies the reaction results in rapid combustion.
How: On a small ball of excelsior in the evaporating dish, sprinkle the sodium peroxide. Drops of water from the medicine dropper on the sodium peroxide start a rapid reaction.
CAUTIONS: Sodium peroxide is caustic in contact with water. The intense fire produced in this demonstration could break the evaporating dish. Smoke is produced. Sodium peroxide should be purchased in small amounts and kept air tight in its original container.
DEMONSTRATION 17:
Spontaneous Fires I
Action: A few drops of liquid from a medicine dropper fall on a mound of powder, in the center of which a small depression has been made. A violent fire flares up.
You Need: Granulated sugar; powdered potassium chlorate; concentrated sulfuric acid.
Why: Dehydration and oxidation of sugar is accompanied by flames.
How: Powder the chemicals separately in a mortar. Place equal volumes of the mixed materials in a mound on an insulated mat. When a few drops of acid fall on the mixture, a reaction produces an immediate fire.
CAUTION: Be careful when working with fire and strong acid!
DEMONSTRATION 18:
Test Tube Fire
Action: A large vertical test tube one-fourth full of a white solid is strongly heated until the material melts. Darkening the room, you extinguish the burner and carefully drop in several pieces of charcoal. The room is lighted up with a bright violet-reddish glow. Carbon particles dance about on the surface of the liquid with a popping sound.
You Need: 25 grams potassium nitrate; charcoal; 200 ml. test tube; spoon.
Why: Oxygen produced by heating potassium nitrate combines rapidly with carbon. The bright violet-reddish glow is characteristic of potassium.
How: To heat the test tube rapidly use a Meeker burner. Oxygen liberated at the high temperature of the molten potassium nitrate unites with carbon with such rapidity that a slight explosion seems to occur. To continue the demonstration heat the test tube as you drop charcoal into the molten material.
Suggestions: Instead of heating potassium nitrate in a test tube you may heat it in a casserole or evaporating dish. Sprinkling powdered charcoal on the molten salt produces a beautiful colored effect.
DEMONSTRATION 19:
Chemical Cannon
Action: You drop a solid and liquid into a large test tube and quickly insert a stopper. Gas pressure will drive the stopper out of the tube with considerable force and with a loud pop.
You Need: Large test tube with cork; five grams sodium carbonate; 10 ml. vinegar.
Why: Carbonates and acid generate carbon dioxide gas, which when confined exerts pressure.
How: Attach the test tube to a ring stand at a slight angle so that you or the audience will not be in the line of fire. A 200 mm. test tube is a good size.
Suggestions and CAUTION: You can generate gases by carbonates and weak acids or by the action of active metals and hydrochloric acid. The cork must be fairly tight to get a loud pop. DO NOT STAND CLOSE TO THE TEST TUBE AS THE GAS IS GENERATED.
Chemical Garden
Action: In a display case stands a large bottle nearly filled with a liquid. A small forest of trees appears to be growing in the liquid.
You Need: Sodium silicate (water glass); large bottle or beaker; large crystals of salts such as cobalt chloride, ferric sulfate, nickel sulfate, manganous chloride, zinc sulfate and chromium nitrate.
Other crystals: alum (potassium aluminum sulfate, copper (II) sulfate
DEMONSTRATION 21:
Freezing Without Cooling
Action: A large Florence flask containing a clear colorless liquid is sitting on the demonstration table. You take a small crystal or two of a white salt and drop it into the flask. A beautiful star-shaped mass of white crystals immediately begins to radiate out from the point of impact, soon completely turning the liquid to a solid white mass. Turning the flask upside down, you show that all the liquid has frozen.
You Need: two- or 3-liter Florence flask; sodium acetate trihydrate
Why: The supersaturated solution of sedum acetate requires only one or two seed crystals of the salt to cause massive crystallization. So much solid is formed that the water is trapped in the mass and appears to be completely frozen.
How: The supersaturated solution is prepared by heating in the flask sodium acetate trihydrate and water, in the ratio of 130 grams: 100 mL, until the salt has dissolved. Make up enough solution to approximately half-fill the flask. Allow the solution to cool slowly without any disturbance.
Remarks: Great care must be taken to avoid jarring the solution lest it crystallize too soon. Place a beaker over the mouth of the flask while it is cooling lest dust particles cause crystallization. This demonstration is a very striking example of the concept of supersaturation.
DEMONSTRATION 22:
Fast Freezing
Action: You place a white powder in a 400 mL beaker. Put the beaker on the wet top of a small inverted wooden box. With rapid stirring, pour 100 mL of water into the beaker. In a minute or two, you lift the beaker and the box comes along with it since it is frozen fast to the beaker.
You need: 100 grams ammonium nitrate; small wooden box such as a chalk box; thermometer reading at least ten degrees below the freezing point of water.
Why: A salt, which absorbs heat on dissolving, lower the temperature of its solution below the freezing point of water.
How: On dropping the powder into the water and stirring rapidly, heat is taken out of the solution and the temperature drops rapidly. The bottom of the beaker is cooled below the freezing point of water. The water below the beaker is frozen. This binds the beaker to the box.
Suggestions: Do not spill any of the salt on the wet top of the box. This will prevent formation of ice where the beaker and box come in contact. Recording the temperature at intervals makes this an interesting class project. The beaker and ice combination can be passed around the class to show the interesting ice formation.
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