[Chemistry Class Notes] on Copper Oxide Pdf for Exam

Here we will introduce and discuss some phenomena involving conduction in copper oxide. Copper is a good conductor of electricity but the natural oxidised form Cu2O is not only an insulator but is also photosensitive (the same goes for most other transition metals). Fortunately, though, that oxide can be easily reduced to copper metal with either heat or electricity. Copper oxide is a good insulator and photo-sensitive but can be easily reduced to the more conductive copper metal by heat or electricity. One of the most prominent properties of conduction in such materials is that it follows the right-hand rule, which states that currents will flow along the path of your right hand’s thumb. Here we will show that this applies not only to the conductivity of metals but also to the photo-sensitivity of insulators like Cu2O.

Basic Principles about Electrical Conductivity

Before we can discuss phenomena involving conduction in copper oxide, it is important that you know some very basic principles about electrical conductivity and what happens to it when an electric current is present. With each moving charge, there is an associated magnetic field (a consequence of Faraday’s law). So a steady flow of electrons in a wire results in a constant and non-zero magnetic field surrounding the wire. If you were to put a compass near the wire, you would notice that your compass needle points along the wire. That is because the magnetic field around the wire is pointing in the same direction as your compass needle.

Placing a Metal Object Next to and Parallel to a Wire

Now we will look at what happens when you place a metal object next to and parallel to a wire and then turn on (or off) electricity into that wire: First, we’ll start with the case where there is no current in the wire. In this case, there is a magnetic field around the wire but a force field or potentially associated with it does not point along with your thumb. We say that this magnetic field is pointing orthogonal to your thumb and we will call this direction “up”.Now, you will notice that it deflects or rotates so that its force field points along with your thumb. We say that the force field has been rotated 90 degrees.

Placing a Metal Object Next to and Perpendicular to a Wire

Similarly, if you place a metal object perpendicular to the wire but on the same side as your thumb, it will be deflected or rotated so that its force field will point out of your fingers. By convention, the direction away from your body is positive. In other words, our thumb points in the direction that current will flow through the wire.

What is Copper(I) Oxide?

Copper Oxide where copper is in liquid form is called cuprous oxide. Cu2O is the chemical structure of cuprous oxide. Well, here in Cu2O copper and oxygen share a covalent bond; hence it naturally has covalent bonds. Crystals of cuprous oxide are found in cubic shape. When you heat the solution of Cu2O in the presence of hydrogen, the solution is reduced quickly. It is disproportionated in the solution of acid and produces copper and copper (II) ions. Cupric oxide, when heated with metallic copper, is turned into cuprous oxide. In the presence of moisture in the air, oxygen reacts with copper on the surface of any object and cuprous oxide can act as corrosion resistance in such conditions. It will serve as the protective layer of oxide that is thin. 

Copper oxide is a pure compound of all variations of copper compounds. It is noticeable because of usability and versatility in physical property. Superconductivity at the higher temperature, effects of electron correlations, and spin dynamics make the copper oxide to be useful in many ways. Also, both properties, i.e. chemical and physical, are very stable and hence can be easily mixed with water solutions or polymers. Furthermore, copper oxide is not expensive. 

Other chemical names used for Copper Oxide: 

• Red Cu2O,

• Cuprous Oxide

• Dicopper Oxide. 

Cu2O Chemical Names: 

• Copper (I) Oxide

• Copper (II) Oxide

Physical Properties of Copper Oxide

Copper Oxide Colour

The Colour of copper oxide is a bit confusing as sometimes you might have seen red or black coloured copper oxides. Well, here you should have a clear idea that there are two types of copper oxides like copper(I) oxide that is black in colour and copper (II) oxide that is red. 

Other Specifications of Cu2O (Copper(I) Oxide)

Density – 6 g/cm³

Molecular Weight/ Molar Mass – 143.09 g/mol

Boiling Point – 1,800 °C

Melting Point – 1,232 C

Chemical Formula of Copper oxide – Cu2O

Copper(I) Oxide Structure – Cu2O

Physical Properties of Copper(I) Oxide – Cu2O

Appearance – Red-coloured solid

Odour – No odour

Covalently-Bonded Unit – 3

The complexity of – 2.8

Heavy Atom Count – 3

Solubility – Insoluble in water

Chemical Properties of Copper(I) Oxide – Cu2O

Copper (I) Oxide can react with water as the oxygen is present in the water and make Copper (II) Hydroxide. Following is the chemical equation to understand the chemical reaction of copper (I) oxide and water. 

2Cu2O + 4H2O + O2 → 4Cu(OH)2

Through the chemical reaction between hydrogen chloride and copper (I) oxide, Copper (I) Chloride is formed. Well, Oxygen of Copper(I) Oxide is reduced with chlorine atoms and form the copper chloride relatively. You can understand the chemical reaction between hydrogen chloride and Cu2O from the below chemical equation. 

Cu2O + 2HCl → 2CuCl + H2O

Uses of Copper Oxide Cu₂O

• The ship’s bottom usually gets affected by seawater, and it is essential to cover the bottom with paint and copper oxide is the best option for antifouling paints. Copper oxide has the property to control corrosion effectively. 

• It is a portion of porcelain paints.

• Photocells for fabricating rectifiers and light meters contain p-type semiconductors that can be carbon oxide. 

• It can be used as seed dre
  ssing and fungicide. 

• They are used in high-tech superconductors, semiconductors and solar-energy transformation. 

• Can be implemented in thermoelectric materials, catalyst, superconducting materials, glass, sensing materials, ceramics and other fields. 

Difference between Cupric and Cuprous Oxide

Copper makes two different oxides according to the valency, Cupric Oxide and Cuprous Oxide. Cupric Oxide is a brown coloured powder while Cuprous Oxide is a red coloured. When an atom of the copper band is attached to an oxygen molecule, then it is Cupric acid. When an oxygen atom is attached to two copper atoms, it is said to be Cuprous Oxide. Cuprous Oxide is mostly in an active state, while Cupric Oxide is in a fully oxidised state. 

How Copper Oxide is Harmless to Human Beings?

Highly reactive molecules are required to kill the bacteria, and copper oxide is a good puller of electrons. It can also release free radicals and also has the ability to destroy any pathogen if found on the surface. Cuprous oxide is unstable and hence acts more quickly than cupric oxide. So, we can conclude that cuprous oxide is safe for humans and toxic for bacteria. Well, size also matters when it comes to the ratio between copper oxide cells and several bacteria. 

Preparation of Cuprous Oxide

The most common way copper (I) oxide is formed is by oxidation of the copper metal.

4Cu + O2 → 2Cu2O

This happens if you leave copper outside in the air. It is slow as hell (like iron rusting). You can speed it up by adding water and certain acids, but it’s still slow. Copper (I) oxide is most commonly made commercially using the other form of copper oxide, copper (II) oxide. You put the copper (II) oxide in a furnace with elemental copper, and a redox reaction takes place, producing copper (I) oxide. Copper (I) oxide can also be made through the electrolysis of an aqueous solution of sodium chloride between copper electrodes.