This experiment involves three chemicals one of which is "free". the other two items can readily be purchased at a hardware store and/or a supermarket. Their individual stories are are amazing enough, but when mixed together they produce something truly amazing!

More amazing yet is the fact that the principles on which this experiment is based are used in a number of commercial products, some silly, some serious.

Borax is a hydrate of sodium tetraborate. It occurs in desert playas where it is shoveled up, cleaned and packaged. It is a water soluble, relatively nontoxic chemical which forms a precipitate with calcium ions. Calcium ions interfere with the action of soap in laundry by precipitating the soap as a sludge, thus destroying its emulsifying properties. Since removing calcium ions improves soap utilization, Borax or chemicals such as sodium phosphate or sodium carbonate which also precipitate calcium ions are frequently added in laundry to act as water softeners or "boosters" or "builders", boosting or building the effect of the soap or detergent.

Elmer's Glue ® and similar products are polymers which can be emulsified in water. The chemical structure involves long chains of carbon atoms, 10,000 or more hooked together in a row, with half the carbons (approximately every other one) having either a hydroxyl (-OH ) group or an acetoxy (-OCOCH₃) group attached. The remaining carbon valences are satisfied by hydrogen atoms. This species is referred to on the label as partially hydrolyzed polyvinylacetate. This polymer is in one sense similar to polyethylene, the material used to make squeeze bottles and plastic wrap. But whereas polyethylene has only carbon and hydrogen atoms and therefore repells water, this glue is emulsified by water. The difference is the presence of the large number of hydroxy groups on the glue molecule which hydrogen bond with water molecules to produce the water emulsion sold as glue. When the water evaporates, the remaining glue molecules form a tough plastic which is particularly good at holding together wood and paper.

So with this background, you will add the two together and try to visualize on a molecular level, how to account for the observed changes.

Oh, by the way, have you figured out the the identity of the "third chemical" mentioned at the beginning? Actually its involvement in this experiment is the basis of some of the more serious applications of the principle involved here.

© RWK 1997

At this point you can start this experiment by going to "hades". Once in hades, at the "username:" prompt, type PRELAB and press Enter. Then follow directions on the screen. If you have a Telnet Application on your computer, to get to hades, simply click on  TO START below. Then type HLAB and follow th directions

Note: before you start, you will need  partially hydrohyzed Polyvinyl Acetate Glue,   saturated Borax solution, a small (3 oz), disposable plastic cup and a stirring stick.  Food dye coloring is optional.