What is Carbon?

Carbon, represented by the symbol “C” and atomic number 6, is a remarkable nonmetallic element and one of the fundamental building blocks of life on Earth. The name derives from the Latin carbo for “charcoal”. It is fourth most abundant element in the universe by mass and second most abundant element in the human body by mass.

Carbon’s strong covalent bonding ability enables the formation of diverse molecules like carbon dioxide (CO₂), methane (CH₄), and organic compounds vital for life, including carbohydrates, proteins, and nucleic acids. Carbon’s role extends to natural cycles like the carbon cycle, which is essential for Earth’s ecosystems.

Carbon Molecular Formula

The molecular formula for carbon is simply “C”. Carbon is an element, hence it only has one type of atom: Carbon. So, its molecular formula is simply “C“.

Carbon Structural Formula

Carbon is a non-metallic tetravalent element that can accept four electrons to form covalent bonds. Having ability to readily form bonds with other atoms and with other carbon atoms, Carbon can form multiple stable covalent bonds with suitable polyvalent atoms.

Carbon has several allotropes, but three naturally occurring allotropes are known to exist: Amorphous, Graphite and Diamond.

The key points about the structural formula of Carbon are:

• The electronic configuration of carbon is 1s², 2s², 2p².
• Carbon has four valence electrons.
• The oxidation states of carbon are +4, +2 and -4.
• This allows for the formation of four single covalent bonds, two double bonds or one double bond with two single bonds and one triple bond with one single bond.
• Examples: Methane (CH₄₎, Carbon dioxide (CO₂),  Ethene (C₂H₄) and Ethyne (C₂H_2).

Physical Properties of Carbon:

• Atomic Number: 6
• Atomic Mass: 12.011 u
• Phase at Room Temperature: Solid
• Appearance: transparent (diamond), opaque (graphite)
• Colour: colourless (diamond), black or grey (graphite), black or brown (amorphous)
• Density: 2.2 g/cm³ at 20 °C
• Melting Point: 3,652 °C
• Boiling Point: 4,827 °C
• Thermal Conductivity: Highest among all known materials (diamond)
• Electrical Connectivity: Good Conductor (graphite)
• Hardness: diamond (hardest known natural substance), graphite (soft and slippery)

Chemical Properties of Carbon:

Carbon is highly unreactive under normal conditions due to its small size and stable compounds.

• Tetravalency: Carbon exhibits a maximum covalence of four in its compounds.
• Catenation: Carbon atoms can bond to each other to form long chains, branched structures, and rings, enabling the creation of complex molecules such as polymers and biological macromolecules.
• Hybridization: Carbon can undergo sp, sp², and sp³ hybridization, leading to different geometries and bonding properties in molecules:
  Tetrahedral geometry : methane (CH₄), Trigonal planar geometry: ethene (C₂H₄) and Linear geometry: ethyne (C₂H₂).
• Allotropy: Carbon exists in several allotropes, including diamond, graphite, graphene, fullerenes, and carbon nanotubes, each with distinct chemical and physical properties.
• Reaction: Carbon compounds undergo four main types of reactions: combustion, oxidation, addition, and substitution.
• Acid-Base Behavior: Carbon compounds can exhibit acidic or basic properties. Carboxylic acids (R-COOH) are weak acids, while amines (R-NH2) are weak bases.
• Formation of Organic Functional Groups: Carbon forms the backbone of organic molecules that contain various functional groups such as hydroxyl (-OH), carbonyl (C=O), carboxyl (-COOH), amino (-NH2), etc.

Uses or Applications of Carbon:

Here are some uses or applications of Carbon:

1. Photosynthesis: Plants use carbon dioxide from the air to produce glucose and oxygen through photosynthesis.
2. Respiration: Living organisms release carbon dioxide as a by-product of cellular respiration.
3. Carbon Cycle: Carbon cycles through the Earth’s atmosphere, oceans and living organisms, maintaining ecological balance.
4. Steel Production: Carbon is a key component in steelmaking, enhancing the strength and hardness of the alloy.
5. Fuel Source: Carbon-based fuels, such as coal, oil, and natural gas, are major energy sources worldwide.
6. Electrodes: Graphite electrodes are used in electric arc furnaces for steel production and other metallurgical processes.
7. Lubricants: Graphite is used as a lubricant in machinery due to its slippery layers that reduce friction.
8. Nanotechnology: Carbon nanotubes and graphene are utilized in advanced materials and electronics for their exceptional strength and conductivity.
9. Filtration: Activated carbon is employed in water and air purification systems to remove contaminants and impurities.
10. Forests: Trees and plants act as carbon sinks, storing carbon in their biomass and helping mitigate climate change.