Carbon
Simplified 2D Bohr model:Central red circle is the nucleus (proton). Blue ring represents the electron's orbit. Small blue dot is the electron. Note: This basic model doesn't show quantum behavior.
CLASSIFICATION:
Nonmetal
Carbon's position in Group 14 of the periodic table categorizes it as a nonmetal. Its four valence electrons enable it to form covalent bonds, sharing electrons with other atoms to achieve a stable octet configuration.
12.011 u
Appearance: Dependent on allotrope: black (graphite), transparent (diamond), etc.
Carbon, the element of life and diversity, is a nonmetallic wonder that forms the foundation of organic chemistry and the intricate molecules that compose living organisms. Its unparalleled ability to form strong covalent bonds and versatile structures through catenation leads to an astounding array of compounds, surpassing any other element. From the crystalline clarity of diamonds to the dark, slippery layers of graphite, carbon's allotropes showcase its remarkable versatility. Its significance extends to modern materials like fullerenes and graphene, revolutionizing fields like electronics and nanotechnology.
6
6
6 (most abundant isotope)
eV
4. Discovery and History
3550 °C (sublimes at standard pressure)
4827 °C
Varies by allotrope: 2.267 g/cm³ (graphite), 3.515 g/cm³ (diamond)
77 pm
5.3 cm³/mol (diamond)
77 pm
Specific per allotrope: 8.517 J/(mol·K) (diamond), 8.527 J/(mol·K) (graphite)
Varies by allotrope: 2000 W/(m·K) (diamond) - among the highest of materials, 119-165 W/(m·K) (graphite)
12,000 m/s in diamond, 18,350 m/s in graphite
Varies by allotrope: 2.267 g/cm³ (graphite), 3.515 g/cm³ (diamond)
10 (diamond) - the hardest known natural material, 1-2 (graphite)
Varies by allotrope: 2000 W/(m·K) (diamond) - among the highest of materials, 119-165 W/(m·K) (graphite)
Varies with allotrope: 70-100 GPa (diamond), 10 MPa (graphite)
Varies by allotrope: 0.509 J/(g·K) (diamond), 0.710 J/(g·K) (graphite)
Specific per allotrope: 1.0 × 10⁻⁶ K⁻¹ (diamond), 7.9 × 10⁻⁶ K⁻¹ (graphite)
N/A
Carbon's reactivity varies significantly depending on its allotropic form and the specific reaction conditions. Diamond exhibits exceptional chemical inertness, while graphite is more reactive, undergoing oxidation and forming intercalation compounds.
+4, +2, -4
Dependent on the specific carbon compound and reaction
Carbon's chemistry is dominated by its ability to form covalent bonds with itself and other elements, leading to an extensive array of organic compounds. Its versatility in bonding and hybridization enables the formation of chains, rings, and complex three-dimensional structures, making it the backbone of life and a cornerstone of chemical synthesis.
Diamagnetic (except for some carbon structures with unpaired electrons, which can exhibit paramagnetism)
Varies significantly by allotrope: extremely low in graphene (one of the most conductive materials known), high in diamond (an electrical insulator)
Dependent on the specific carbon structure and its electronic properties
2.417 (diamond) - High refractive index contributes to diamond's brilliance and ability to disperse light.
Superior in diamond, variable in other allotropes depending on their structure and surface properties
Varies widely among different carbon allotropes, with each form exhibiting characteristic absorption bands in different regions of the electromagnetic spectrum.
n = 2 for carbon's valence electrons, indicating their location in the second energy level (l = 0 for the 2s orbital, l = 1 for the 2p orbitals, determining the shapes of the electron orbitals and influencing carbon's bonding behavior)
Total Electrons: 6, Shells: 1s², 2s² 2p²
-1086.5 kJ/mol for the first ionization energy, representing the energy required to remove one electron from a neutral carbon atom
[He] 2s² 2p²
Carbon's electron configuration, with four valence electrons in the 2s and 2p orbitals, underlies its ability to form four covalent bonds and adopt various hybridization states (sp³, sp², sp), leading to the diversity of organic compounds and carbon-based materials.
Cosmic and Terrestrial Abundance
Carbon is the fourth most abundant element in the universe by mass, formed in the cores of stars through nuclear fusion. On Earth, carbon is found in various forms, including: * **Elemental forms:** Diamond and graphite are naturally occurring allotropes of carbon, formed under specific geological conditions. * **Carbonates:** Limestone, marble, and dolomite are sedimentary rocks composed primarily of calcium carbonate (CaCO3). * **Fossil fuels:** Coal, petroleum, and natural gas are carbon-rich fuels formed from the remains of ancient organisms. * **Organic matter:** Carbon is the fundamental building block of all living organisms and is present in various organic compounds, including carbohydrates, proteins, and fats.
Diamond Cubic
Temperature: Stable at standard conditions
Diamond's crystal structure features a three-dimensional network of carbon atoms, each bonded to four neighboring atoms in a tetrahedral arrangement. This robust structure contributes to diamond's exceptional hardness and thermal conductivity.
Hexagonal
Temperature: Stable at standard conditions
Graphite's crystal structure consists of layers of carbon atoms arranged in a hexagonal lattice. These layers are held together by weak van der Waals forces, allowing them to slide past each other, giving graphite its characteristic slippery texture and making it a good lubricant.
+4, +2, -4
Carbon's most common oxidation state, reflecting its ability to share all four valence electrons in covalent bonds with more electronegative elements, as seen in carbon dioxide (CO2) and carbon tetrachloride (CCl4)., Less common than +4, the +2 oxidation state occurs when carbon shares two of its valence electrons, as observed in carbon monoxide (CO) and some organometallic compounds., The -4 oxidation state arises when carbon gains four electrons, typically in bonds with less electronegative elements, such as hydrogen in methane (CH4).
Carbon Dioxide (CO2)
CO2
A colorless, odorless gas vital to life on Earth, carbon dioxide is a product of respiration and combustion. Plants utilize it during photosynthesis to produce organic compounds and release oxygen, maintaining the delicate balance of atmospheric gases.
Methane (CH4)
CH4
The simplest hydrocarbon, methane is a potent greenhouse gas and a primary component of natural gas. It is also produced by methanogenic microorganisms in various environments, including wetlands and the digestive tracts of ruminant animals.
Acetylene (C2H2)
C2H2
A colorless gas with a characteristic odor, acetylene is widely used as a fuel and chemical building block. Its high flame temperature makes it suitable for welding and cutting metals, while its reactive triple bond makes it a versatile starting material for organic synthesis.
Calcium Carbonate (CaCO3)
CaCO3
A ubiquitous compound found in limestone, marble, and shells, calcium carbonate is a cornerstone of construction materials and plays a crucial role in geological processes.
Glucose (C6H12O6)
C6H12O6
A simple sugar and a primary source of energy for living organisms, glucose is a building block of carbohydrates and plays a central role in cellular respiration.
Sucrose (C12H22O11)
C12H22O11
Commonly known as table sugar, sucrose is a disaccharide composed of glucose and fructose units. It is widely used as a sweetener and food additive.
Cellulose ((C6H10O5)n)
(C6H10O5)n
A complex carbohydrate and the main structural component of plant cell walls, cellulose is the most abundant organic polymer on Earth.
156.1 nm nm
Strong
Ultraviolet
165.7 nm nm
Strong
Ultraviolet
193.1 nm nm
Medium
Ultraviolet
Renowned for its exceptional hardness, brilliance, and thermal conductivity, diamond is a crystalline allotrope of carbon with a tetrahedral arrangement of carbon atoms. Its unique properties make it highly valued as a gemstone and industrial material.
A soft, black, and slippery material, graphite consists of stacked layers of carbon atoms arranged in a hexagonal lattice. Its electrical conductivity and lubricity make it suitable for use in pencils, electrodes, and lubricants.
Fullerenes are molecules composed entirely of carbon atoms arranged in closed cages or tubes. The most well-known fullerene is Buckminsterfullerene (C60), a spherical molecule resembling a soccer ball. Fullerenes exhibit unique properties and have potential applications in various fields, including materials science, electronics, and medicine.
A single layer of carbon atoms arranged in a two-dimensional honeycomb lattice, graphene is known for its exceptional strength, electrical conductivity, and flexibility. Its remarkable properties make it a promising material for various applications, including electronics, energy storage, and composite materials.
Amorphous carbon lacks a long-range ordered structure and can exist in various forms, including charcoal, soot, and carbon black. These materials find applications in filters, pigments, and rubber reinforcement.
Carbon nanotubes are cylindrical structures composed of rolled-up sheets of graphene. They exhibit exceptional strength, electrical conductivity, and thermal properties, making them suitable for applications in nanotechnology, electronics, and materials science.
17. Practical Applications
Filtration
Activated carbon, with its high surface area and porosity, is an effective adsorbent used in water and air purification systems to remove contaminants, odors, and impurities.
Reinforcement Material
Carbon fibers, known for their exceptional strength and lightweight properties, are used to reinforce composite materials, finding applications in aerospace, automotive, sporting goods, and construction industries.
Semiconductors
Graphene, a single layer of carbon atoms arranged in a honeycomb lattice, exhibits remarkable electrical conductivity and strength, making it a promising material for next-generation electronics, including transistors, sensors, and energy storage devices.
Energy
Fossil fuels, such as coal, petroleum, and natural gas, are carbon-based energy sources that have powered industrial development and modern society. However, the environmental impact of burning fossil fuels necessitates a transition to cleaner and more sustainable energy sources.
Medicine and Pharmaceuticals
Carbon-based compounds form the basis of many drugs and pharmaceuticals. Carbon materials are also being explored for use in drug delivery systems and medical implants.
Materials Science
Carbon's versatility leads to a wide range of materials with diverse properties. From diamond's hardness to graphite's lubricity, carbon materials find applications in cutting tools, lubricants, electrodes, and structural components.
26. Synthesis and Production
Synthesis methods for carbon allotropes vary widely: * **Diamond:** Synthetic diamonds are produced through high-pressure, high-temperature (HPHT) processes or chemical vapor deposition (CVD). * **Graphite:** Synthetic graphite is produced by heating carbon-containing materials to high temperatures under controlled conditions. * **Fullerenes:** Fullerenes are typically synthesized by vaporizing carbon-rich materials using laser ablation or electric arc methods. * **Graphene:** Graphene can be produced by mechanical exfoliation of graphite, CVD, or epitaxial growth on certain substrates.
N/A
N/A
20. Economic Data
Market Price: Variable, depending on the form and purity
Producing Countries: China, India, Russia, and the United States are among the top producers of carbon-based materials, including coal, petroleum, natural gas, and graphite.
Industrial Use: Carbon and its compounds have extensive industrial applications, including: * **Energy production:** Fossil fuels remain a primary energy source. * **Materials science:** Carbon fibers, graphene, and other carbon materials find use in composites, electronics, and construction. * **Chemical industry:** Carbon is a fundamental building block for various chemicals, polymers, and pharmaceuticals. * **Environmental technologies:** Activated carbon is used in filtration and purification processes.
Description: N/A
18. Biological Role
Basis of Life
Carbon is the defining element of life, forming the backbone of organic molecules essential for all known living organisms. Its ability to form stable covalent bonds and versatile structures enables the complexity and diversity of biomolecules, including: * **Carbohydrates:** Sugars, starches, and cellulose provide energy and structural support. * **Proteins:** Amino acids linked together form proteins, which perform a wide range of functions in cells, including catalysis, transport, and signaling. * **Lipids:** Fats and oils store energy, provide insulation, and form cell membranes. * **Nucleic acids:** DNA and RNA carry genetic information and control cellular processes.
Regulations related to carbon primarily focus on environmental aspects, such as controlling carbon emissions, managing air quality, and ensuring the safe handling and disposal of carbon-containing materials. Regulations also exist for specific carbon compounds, such as carbon monoxide and certain organic solvents, due to their potential health and environmental hazards.
Legal restrictions on carbon-related activities often involve emissions trading schemes, carbon taxes, and regulations on industrial processes and energy production to mitigate climate change and reduce air pollution.
19. Health and Environmental Impact
Exposure to certain forms of carbon can have adverse health effects, including respiratory problems, cardiovascular disease, and cancer. Carbon monoxide poisoning is a serious health risk, while exposure to fine particulate matter from combustion sources can contribute to respiratory and cardiovascular issues.
Carbon dioxide emissions from human activities, primarily the burning of fossil fuels, are the main driver of climate change. Methane is also a potent greenhouse gas, contributing to global warming. Sustainable carbon management, including reducing carbon emissions, carbon capture and storage, and transitioning to cleaner energy sources, is crucial for mitigating climate change and its environmental consequences.
27. Environmental Safety
Exposure to carbon dust, particularly fine particulate matter, can pose respiratory hazards, leading to conditions like black lung disease. Carbon monoxide (CO), a colorless and odorless gas, is highly toxic, interfering with oxygen transport in the blood. Certain carbon compounds, such as benzene and polycyclic aromatic hydrocarbons (PAHs), are known carcinogens.
Appropriate safety measures should be taken when handling carbon materials, including the use of respiratory protection, proper ventilation, and adherence to safety guidelines for specific carbon compounds. Monitoring and controlling carbon emissions are essential for environmental protection and mitigating climate change.
Handling: N/A
Storage: N/A
First Aid Measures: N/A
23. Future Predictions
Advancements in Carbon-based Technologies
Continued research and development in carbon-based materials, such as graphene, carbon nanotubes, and fullerenes, are expected to lead to breakthroughs in electronics, energy storage, materials science, and nanotechnology. These advancements hold promise for creating lighter, stronger, and more efficient devices and materials.
Sustainable Carbon Management
The development and implementation of sustainable carbon management strategies, including carbon capture and storage, carbon sequestration, and the transition to renewable energy sources, will be essential for addressing climate change and reducing carbon emissions.