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
Oxidation reactions occur when the reactant loses electrons and may involve the addition of oxygen or the loss of hydrogen, while reduction reactions occur when the reactant gains electrons and may involve the loss of oxygen or the addition of hydrogen. In oxidation, the atom or molecule becomes more positively charged, while in reduction, the molecule becomes more negatively charged.Full Answer >
In sodium bromide, NaBrO3, the oxidation state of sodium is 1+, bromide is 5+, and oxygen is 2-. The oxidation states in a molecule are important when it comes to understanding the oxidation-reduction reactions that occur in a chemical reaction. In oxidation, there is an increase in oxidation numbers whereas in reduction, oxidation states decrease.Full Answer >
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 >