To illustrate the concept of density of liquids to students, mix oil and vinegar. You'll need a see-through plastic bottle and perhaps some food coloring to mix with the vinegar to show where it is located more clearly. Pour the vinegar into the bottle first. Add a few drops of the food coloring to the vinegar. Shake to mix. Then pour in some oil. Let other students shake vigorously to mix the two liquids. Then let the mixture settle for a few minutes. The oil will rise above the green-colored vinegar as it is less dense. For a twist, let students shake the bottle again, hold it upside down and let it settle that way for a few minutes. The vinegar will again be below the oil layer.
As vinegar acid dissolves eggshells, the eggs will bounce instead of smash. On day one, give each student an egg. Then allow them to drop their eggs to see them smash (do this outside where cleanup is easier). Each kid then gets an egg, some vinegar and a cup. Ask each student to place his egg in the cup and cover it completely with vinegar. After four days, the eggshell will have been dissolved by the vinegar. Remove the eggs and drain them on kitchen towel. Tell students to drop the eggs from a height of two inches. Then have the class compete to see which egg bounces from the highest height. The winner's prize can be a chocolate Easter egg if they are in season.
Using the power of carbon dioxide bubbles, this bomb-type experiment should be done outside. The materials students will need include a plastic bag with a zip-type closure, kitchen towel, 1 1/2 tbsp. baking soda, 1/2 cup of vinegar and 1/4 cup of warm water. Fold up the baking soda in a 5-inch square piece of kitchen towel to make a packet. Place the vinegar and water into the bag. Drop in the packet of baking soda, and quickly zip the bag closed. After a quick shake, the bag will puff up and explode with the production of carbon dioxide from the reaction between the acidic vinegar and the base baking soda.
This experiment shows how vinegar and two opposing metals produce an electric current in a makeshift battery. You'll need a film canister container with a lid, 3 inches of a 14 gauge copper wire, a 2-inch galvanized nail, vinegar and a voltmeter. Insert the wire into one side of the lid, the nail into the other side. Dip the tips into the vinegar in the canister. The copper wire is the positive terminal, and the nail is the negative terminal. Connect the voltmeter to these terminals to measure the voltage produced by the battery.