[Chemistry Class Notes] on Carbon Pdf for Exam

Carbon is one of the most important elements of life. Without this, the existence of life could not have been made possible. You may have noticed, that carbon is the primary element in most compounds that are necessary to live. In the study of climate change, carbon is often and generally termed carbon dioxide. It is the primary greenhouse gas that is emitted by humans. However, from the technical perspective, carbon becomes carbon dioxide only if an atom joins two oxygen atoms. This makes the chemical formula appropriate – CO2.

                                 

                                  

In this article, we will briefly discuss carbon. It is an important element. Characteristics of carbon, chemical properties, applications, importance, and role of carbon are discussed below in detail.

Characteristics of Carbon

Some characteristics of carbon are given below: 

• Carbon makes 4 electrons to form a covalent bond.

• It has a number of allotropes and other forms of existence. These include diamond and graphite with distinctive properties.

• Carbon is highly unreactive under conditions that are normal.

• This chemical element is represented with the symbol C.

• It contains 6 protons in the nucleus and thus has the atomic number 6.

• Carbon is both nonmetallic and tetravalent.

• It is available in various shapes.

• The chemical element has the ability to bond with multiple elements.

Chemical Properties 

The chemical properties of carbon are as follows:

• The atomic number of carbon is 6.

• The atomic mass of carbon is 12.011 g.mol-1. The electronegativity is 2.5.

• The density of the carbon atom is 2.2 g.cm-3 at 20°C.

• The melting and boiling point of carbon is 3652 °C and 4827 °C, respectively.

• The Van der Waals radius is 0.091 nm.

• The Ionic radius of the carbon atom is 0.015 nm (+4); 0.26 nm (-4).

• The electronic shell of the carbon atom is [He]2s22p2.

• The energy of the carbon atom’s first, second, and third ionisation is 1086.1 kJ.mol-1, 2351.9 kJ.mol-1, and 4618.8 kJ.mol-1, respectively.

• The carbon atom was discovered by Antoine Lavoisier.

Applications of Carbon

It is a free element that comes with lots of uses. The uses of carbon and its compounds are as follows:

• These include decorating with pieces of diamond or black pigment in the rim of automobiles or ink of printer. 

• Graphite is another form of carbon that has been used for crucibles of high-temperature, arc lamp electrodes, dry cells, or for pencil tips. 

• There is another amorphous state of carbon, known as vegetal carbon which is used in the form of bleaching agent and gas absorbent.

• The compounds of carbon have numerous uses. For the carbonization of drinks, they use carbon dioxide and fire extinguishers. 

• Dry Ice is the solid form of carbon. Carbon monoxide is useful for the reduction in a number of metallurgic processes. 

• When it comes to industrial solvents, carbon disulphide and carbon tetrachloride are some of the notable inclusions. 

The Physical and Biological Role of Carbon

On the basis of weight, carbon comes in number 19th in the order of elemental abundance. It has been estimated that there are at least 3.5 times as many carbon atoms as silicon atoms in the universe. Apart from carbon, only helium, oxygen, hydrogen, nitrogen, and neon are automatically abundant in the cosmos. Carbon is the cosmic product when helium is burnt. In this process, three helium nuclei with atomic weight 4, get fused to produce a carbon nucleus with atomic weight 12.

In the Earth’s crust, elemental carbon is a minor complement. However, carbon compounds like carbonates of calcium, magnesium help in the formation of common minerals like dolomite, magnesite, limestone, and marble. Moreover, shells of clams, oysters, and corals are actually calcium carbonate. Carbon is distributed to a great extent in the form of coal and organic compounds. They constitute natural gas, petroleum, and plant and animal tissue. Carbon is an important component in the process of photosynthesis. It is a natural sequence of chemical reactions that involve the conversion of the carbon cycle to form atmospheric carbon dioxide and carbohydrates.

The Chemical Reactivity of Carbon

The compounds of carbon form the basis of life on Earth, and the cycle of nitrogen carbon provides the energy that is produced by the Sun and stars. Carbon has a rapport of bonding with smaller atoms, including those which are carbon itself. This is made possible with the formation of stable and covalent bonds. 

Well, it’s true that carbon is present in almost every compound, but the chemical reactive properties are very weak when compared with other elements. The comparison has been made under normal conditions. If we consider standard pressure and temperature, carbon has the ability to resist oxidation. Therefore, it will not react with sulfuric acid, chlorine, hydrochloric acid, and other alkali metals. However, increasing the temperature, carbon will react with oxygen and metals to form carbon dioxides and metal carbides, respectively. 

Carbon can form very long chains which are not only strong but also stable, interconnected C–C bonds. Carbon and its compounds lesson describe that this is the reason behind the formation of an infinite number of compounds. In fact, the count is huge when it comes to carbon co
mpounds compared with other chemical elements. However, hydrogen is the only exception as almost all organic compounds contain the gaseous substance. 

A Detailed Analysis of Carbon

Carbon is unique because of its chemical properties. One of the most interesting parts of the story is that the total components are superior to the whole number of compounds formed from other elements together. One of the biggest groups of these components is formed when hydrogen combines with carbon. The number of organic components is a minimum of 1 million that are known to us, and the number increases dramatically on a yearly basis. The classification may not be fixed, but carbon continues to form a different series of compounds that are inorganic. The number is quite reduced when compared with organic compounds.

There are a couple of allotropic crystalline states of elemental carbon. These are graphite and diamond. A bit decreased form of crystalline compounds are black fume and vegetal carbon. The pure form of carbon through the chemical process could be prepared with the help of sugar through thermal decomposition without the existence of air. Both chemical and physical properties are based on the crystalline structure of that particular element.

Carbon and its Function

The density of carbon keeps fluctuating like 2.25 g/cm³ or 1.30 ounces/in³ in graphite and it is 3.51 g/cm³ or 2.03 ounces/in³ in a diamond. Graphite’s melting point is 3500℃ or 6332℉. The boiling point in the extrapolated form is 4830℃ or 8726℉. Elemental carbon property is inert and thus, it’s insoluble in bases, water or diluted acids, and even organic solvents. However, at higher temperatures, it can bind with oxygen through which carbon monoxide and carbon dioxide are formed. When carbon reacts with oxidizing agents such as nitric acids, metallic acids, and potassium nitrate, C6(CO2H)6 is formed. Considering the halogens, fluorine only makes the reaction to elemental carbon. Several metals bind with this element at different degrees of temperature to come up with carbides.

Importance of Carbon

Carbon is a compound that can be found in almost all living things. This is the reason it plays a vital role in the category of organic compounds. It makes up the life process by making up other cells and structures of an organism. Carbon is a primary element when it comes to organic compounds. Therefore, carbon is essential for living.

Diamonds and graphite are examples of their purest form. Carbon can easily form a molecule by combining with other elements. The molecules are carbon based and they form the basic building blocks of humans, plants, animals, soils, and trees. CO2 and methane are a form of greenhouse gas that consists of molecules that are carbon based. These properties can also be found in fossil fuels. These molecules are made of hydrocarbons that consist of hydrogen and carbon.

Conclusion

Carbon is a unique element because of its ability to form strongly bonded chains. The compounds of carbon are found everywhere; therefore, it becomes essential for living organisms. The above article explained all the details related to carbon and provided a strong concept on this topic.