Propriedades do carbono: Uma visão geral abrangente

In the world of elements, carbon is unique and dazzling. From organic molecules, the basis of life, to key materials for industry, it’s everywhere. Exploring the properties of carbon gives us insight into the intersection of nature and technology, the composition of matter and chemical reactions.

Physical Properties of Carbon

Overview of allotropes

Carbon can form a variety of allotropes, such as diamond, graphite, etc. Although they are composed of carbon atoms, but the atomic arrangement and connection modes are different. The physical and chemical properties are significantly different, and the application research value is high in materials, electronics and other fields.

Diamond characteristics

Diamond is the hardest substance in nature, with a Mohs hardness of 10. Its atoms are tetrahedral structure, strong atomic binding force, wear resistance and pressure resistance, used for cutting drilling. It is colorless and transparent, refractive strong, is a gem. High thermal conductivity, you can use it for electronic heat dissipation, but hardly conductive.

Graphite properties

The texture of graphite is soft and smooth. It comes from the layered structure and is easy to slip between layers. You can often use graphite as a lubricant under high temperature and high pressure. It has good electrical conductivity, free electrons in the layer. And you can use graphite in lithium-ion battery ânodo materials and motor brushes to ensure charge and discharge and current transmission.

Other allotrope characteristics

Fullerenes such as C60 are caged, optically active, can form complexes with metal ions, and have potential in optoelectronic devices and catalysis. Carbon nanotubes have nanometer diameter, high strength, good electrical and thermal conductivity. And you can use it in the field of nanoelectronics and composite materials. Graphene is a single-layer two-dimensional material with excellent electrical, mechanical and thermal properties. And it has broad prospects in flexible electronic devices.

General physical properties summary

Appearance

The diamond is colorless and transparent, bright after polishing, and is a gem material. Grafite dark gray with metallic luster, flaky, smooth touch. Fullerenes are black or brown powder, carbon nanotubes are extremely thin black tubes. And graphene is a nearly transparent, two-dimensional sheet with a distinctive wrinkled texture.

Densidade

Diamond about 3.5-3.53g/cm3, atoms tightly packed; Graphite about 2.09-2.23g/cm3, there is a gap between the layers. Fullerenes are about 1.65g/cm3, carbon nanotubes are 1.3-1.4g/cm3, and graphene is about 2.267g/cm3, with densities varying depending on atomic arrangement and structure.

Ponto de fusão

The melting point of diamond exceeds 3500°C, and the atoms form regular tetrahedrons with covalent bonds, and the structure is solid. The melting point of graphite is about 3652-3697°C, and the covalent bond in the layer is stable. The high melting point makes the carbon stable in high temperature environment and is used in high temperature industrial fields.

Boiling point

Diamond and graphite boiling point are about 4827°C, under normal conditions. Carbon is difficult to change from solid to gas, extremely high temperature to change the state. In the industrial and living environment, carbon physical and chemical properties are stable, not easy to volatilize decomposition.

Solubilidade

Carbon is insoluble in water, common organic solvents and acid and alkali solutions. Because of its stable atomic structure and strong interatomic force, the solvent molecule is difficult to break the carbon elemental structure and its action. And the solubility is extremely low in most solvents.

Conductivity

The graphite layer structure has free electrons, conducts electricity well, and you can use it for electrodes. Diamond electrons are bound to covalent bonds and hardly conduct electricity. Fullerenes and carbon nanotubes have certain electrical conductivity, graphene has high electron mobility, excellent electrical conductivity, and great potential in the electronic field.

Chemical properties of carbon

Stability

At room temperature, the chemical properties of carbonization are stable. The four electrons in the outermost layer of its atom are not easy to gain or lose electrons. Requiring large energy to break the stable structure and participate in chemical reactions. So carbon-containing cultural relics, paintings and paintings can be preserved for a long time.

Flammability

It is flammable and completely burns to produce carbon dioxide when oxygen is sufficient, releasing a lot of heat energy. Carbon monoxide is produced from incomplete combustion when oxygen is insufficient, and combustion reaction is an important way to obtain energy.

Reducibility

It has significant reducibility at high temperatures. It can react with metal oxides, seize the oxygen in the oxides, and reduce the metal. You can widely use it in metal extraction in the metallurgical industry and it plays a key role.

Reactions with other substances

It reacts with a variety of substances under certain conditions. At high temperatures, it reacts with sulfur to produce carbon disulfide, reacts with water vapor to produce carbon monoxide and hydrogen. And the products have important applications in chemical and fuel fields.

Quadrivalence

The four outermost electrons of a quaternary carbon atom are in a quaternary state. It can form 4 covalent bonds with a variety of atoms to build complex and diverse compounds, from simple organic matter to biological macromolecules. It is the basis of the organic world and living matter, and is of great significance.

Chaining

Its atoms can be linked to chains through covalent bonds, that is, chaining. It an form straight chain, branch chain or ring structure, chain length and structure affect the properties of compounds. It is the basis of the formation of many organic compounds, supporting the huge system of organic chemistry.

Electronic structure

The electron configuration of a carbon atom is 1s22s22p2. This structure determines its chemical behavior, and the four outermost electrons make it easy to share electrons with other atoms to form bonds. But also to gain and lose electrons under certain conditions, and participate in various chemical reactions.

Electronegativity

It has a electronegativity of about 2.55 (on the Pauling scale), between metals and nonmetals. In a compound, when bonding with different elements, the chemical bond has different polarity due to the electronegativity difference. It affects the chemical activity and physical properties of the compound.

Connection between property and application

Applications determined by physical properties

Its physical properties are diverse, which makes it rich in applications. Diamond hardness is called the crown of nature, and has significant advantages in the field of cutting and grinding. Such as cutting glass and processing cemented carbide. Graphite has good electrical conductivity and you can widely use it in battery electrodes to ensure charge and discharge cycle. Graphene has excellent electrical conductivity and ultra-high flexibility, making it an ideal material for flexible display screens and wearable electronic devices. The high strength of carbon nanotubes can enhance the performance of composite materials. And you can use it in fields such as aerospace, where the strength of materials is demanding.

Applications determined by chemical properties

Its chemical properties dominate its application in a number of key areas. Flammability makes coal and natural gas become important energy sources. Burning to release a lot of heat energy to meet the energy needs of industrial production and daily life. Reducibility makes it play a key role in the metallurgical industry, reducing metals from their oxides. The quadrivalence and chain ability of átomos de carbono are the basis for the construction of organic compounds. And the synthesis of drugs, plastics, rubber, etc., rely on this, providing a rich variety of products for modern society.

Conclusão

Carbon plays an important role in nature and human society by virtue of its unique properties. Its allotrope properties determine a wide range of applications, and its chemical properties support life and industry. In the future, its research will deepen and continue to help solve problems such as energy.