SHOPPING LIST AND SOLUTIONS

D-cell battery and battery holder (the holder is not absolutely necessary) 

Caution Some fumes will be generated during this preparation, so work in an open area as you would if you were working with solvents, varnish, or paint thinner. The fumes are nitrogen-oxygen compounds such as those present in smog. 

Put on garden gloves (a must) and then tear off about a cubic inch (20 milliliters) of fine steel wool. This is about as much as you can tear off in one healthy pinch. Put the steel wool in the vinegar, and cover the cup with plastic wrap. Label the cup iron acetate and add your name and the date. The solution will be ready for use after sitting overnight. Save the solution with the steel wool still in it, as it will be used in a couple of demonstrations. 

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To see how this works, put on your safety glasses and then add about a tablespoon (15 milliliters) of purple-cabbage indicator (prepared as outlined in the Shopping List and Solutions ) to a cup (240 milliliters) of water and observe the color. It should be light lavender. Now make up a saturated solution of baking soda in water. A saturated solution is one in which no more solid can be made to dissolve. Baking soda is not very sol-... 

Now take some of the clear, carbonated soda that was a suggested purchase in the Shopping List and Solutions and add the purple-cabbage indicator. You should observe a pale pink solution. Carbonated soda... 

Adjust your safety glasses comfortably over your eyes, and then add a tablespoon (15 milliliters) of baking soda to a half cup of water (120 milliliters) and stir. Allow the undissolved material to settle to the bottom (this should take about a minute), and then carefully pour off the clear liquid into another glass, leaving the solids. Pour a tablespoon (15 milliliters) of the copper sulfate solution described in the Shopping List and Solutions into the decanted baking soda solution. Beautiful blue flakes should immediately form and settle out of solution. You should also see some bubbles, and the supernatant, the liquid over the blue blob precipitate, should be a pastel blue. The bubbles are from excess acid in the copper solution reacting with the bicarbonate ion. 

With safety glasses securely in place, add a teaspoon (5 milliliters) of hydrogen peroxide to a quarter cup (60 milliliters) of iron acetate solution (see the Shopping List and Solutions ). The solution should turn a nice reddish brown as the ferrous ion becomes the ferric ion. Slowly add a half cup (120 milliliters) of cold, brewed brown tea. You should get a black, mushy precipitate that will eventually settle to the bottom. Historically, this material was used as black ink, and this precipitation reaction was used to produce it. 

To demonstrate this effect, put on your safety glasses then take a plastic sandwich bag and put in about two teaspoons (10 milliliters) of the sour salt (citric acid) suggested for purchase in the Shopping List and Solutions. Then put one tablespoon (15 milliliters) of water into the bag and seal it up. The bag will feel cold to the touch as the sour salt dissolves. The effect is most pronounced at the beginning of the dissolution. To give... 

Two major factors that affect the rate of a chemical reaction—the kinetics of the reaction—are concentration and temperature. The effects of both are easily demonstrated using items from our Shopping List and Solutions. ... 

Put on your safety glasses, then set up the cups with bleach as before, but this time expose one of the solutions to the black light suggested for purchase in the Shopping List and Solutions. The black light should be moved to within an inch of the solution s surface for maximum effect. The... 

If you let your crystals dry overnight, then find your safety glasses again and put them on. Take about a quarter of either the wet or dry acetylsalicylic acid crystals and place them into a glass container that can be used for warming. The dried crystals are very fluffy and should be handled carefully so they do not scatter. Take the bottle of aquarium pH-lowering solution recommended for purchase in the Shopping List and Solutions, and add it dropwise until the entire sample of acetylsalicylic acid is com-... 

Now, making certain your safety glasses are in place, take the iron acetate solution mentioned in the Shopping List and Solutions and put a puddle of it, about a half inch (about 1 centimeter) in diameter, on a dry ceramic or glass plate. Take care that the puddle does not smear. If the puddle clearly has a raised top, rounded by surface tension, then you are... 

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