The simplest way to tell if something is copper is by its appearance, which is a unique reddish tone before oxidation. Its color turns green when oxidized. Copper also has several other notable properties, such as a high level of thermal and electrical conductivity, as well as specific strengths against a variety of stresses. Copper is extremely common in human use, both in piping in its pure form and in alloys such as brass and bronze in such forms as doorknobs and sculptures.
If an object's appearance does not show that it is copper, or if someone suspects that it is just a copper plating or paint, there are other ways to check. The least destructive ways are to weigh it, or to check its electrical conductivity. Copper weighs about 0.3 ounces per cubic centimeter, so if one have an easy way to calculate the volume of material, he will be able to predict a copper object's weight. The electrical standard potential of copper is either 0.522 volts or 0.345 volts, depending on the type. This may be misleading, however, because a thick enough coating of copper will conduct electricity by itself. Pure copper is relatively soft and is easily scratched with common steel tools.Learn More
The oxidation number for zinc is +2. When zinc becomes oxidized, it is called zinc oxide. When zinc oxidizes, the zinc atoms join with an oxygen atom creating the chemical formula ZnO and the oxidation causes zinc to crystallize into either a hexagonal or cubical shape.Full Answer >
Oxidation numbers are assigned using a strict set of rules. The rules state that each atom in its elemental form has an oxidation number of zero. Another key rule states that ions have oxidation numbers equal to their individual charges.Full Answer >
According to About.com expert Dr. Anne Marie Helmenstine, the simplest way to determine if an element is a metal is to see if it appears with the other metals on the periodic table. There are 117 non-theoretical elements on the periodic table, and all but 17 are either metals or metalloids. Scientists also use chemical experiments to determine if a sample of indeterminate nature contains metal ions.Full Answer >
Chlorine gas is greenish yellow in appearance. The word “chlorine” comes from the Greek word “chloros,” meaning greenish yellow. This element is a halogen belonging to group 17 on the periodic table. Its chemical symbol is Cl, and it has an atomic weight of 35.453 grams per mole.Full Answer >