Metals are fantastic conductors of electricity. Using aluminum foil, a flashlight battery and a C or D sized battery students can check for metal objects in the classroom or at home. Create a ribbon of aluminum foil. Tape one end of the ribbon to the flat side of the battery and wrap the other end around the bottom of the light bulb. To test for metal, place the positive side of the battery, the one with the bump, against the object. If it is metal it will light up. In some cases metal will not light the bulb if it is painted or has other coatings.
Create a solution of vinegar and table salt. Place 10 to 15 pennies in the solution and remove them after five minutes. The students will notice the pennies are cleaner than when they went in. This is because oxidized copper has been removed from the surface. Place an iron nail into the vinegar and salt solution the pennies were in and let it sit for half an hour. Bubbles will form around the nail and eventually a small layer of copper will form on the nail. This is the copper that was removed from the pennies. This leads to the reactivity of metals.
Metals react with each other and are great conductors of electricity. These two characteristics make batteries possible. Students can make batteries using two strips of metal and an acid. A simple battery uses a strip of aluminum or zinc and copper, some soda and a volt meter. Pour the soda into a container and place the metal strips on opposite sides of the container. Connect the volt meter to read the amount of volts. Other popular methods include using potatoes and lemons as the acidic medium to conduct the electricity.
Not all metals react the same way. To test this, get a few metal items such as iron nails, copper pins or tacks, galvanized nail and an aluminum nail. Place each nail in a test tube and cover with hydrochloric acid (HCl). Hydrochloric acid must be handled with care. Each of the metals will react with the HCl and create hydrogen gas. To test this, light a splint and hold it over the test tube. The hydrogen gas will ignite. The larger the amount of hydrogen gas present the more aggressive the ignition.